GCC 3.4 Release Series — Changes, New Features, and Fixes - GNU Project - Free Software Foundation (FSF)

# GCC 3.4 Release Series
Changes, New Features, and Fixes

The latest release in the 3.4 release series is GCC 3.4.3.

GCC 3.4 has many improvements in the C++ frontend. Before reporting a bug, please make sure it's really GCC, and not your code, that is broken.

## Caveats

- GNU Make is now required to build GCC.
- With `-nostdinc` the preprocessor used to ignore both standard include paths and include paths contained in environment variables. It was neither documented nor intended that environment variable paths be ignored, so this has been corrected.
- GCC no longer accepts the options `-fvolatile`, `-fvolatile-global` and `-fvolatile-static`. It is unlikely that they worked correctly in any 3.x release.
- GCC no longer ships `<varargs.h>`. Use `<stdarg.h>` instead.
- Support for all the systems obsoleted in GCC 3.3 has been removed from GCC 3.4. See below for a list of systems which are obsoleted in this release.
- GCC now requires an ISO C90 (ANSI C89) C compiler to build. K&R C compilers will not work.
- The implementation of the MIPS ABIs has changed. As a result, the code generated for certain MIPS targets will not be binary compatible with earlier releases.
- In previous releases, the MIPS port had a fake "hilo" register with the user-visible name `accum`. This register has been removed.
- The implementation of the SPARC ABIs has changed. As a result, the code generated will not be binary compatible with earlier releases in certain cases.
- The configure option `--enable-threads=pthreads` has been removed; use `--enable-threads=posix` instead, which should have the same effect.
- Code size estimates used by inlining heuristics for C, Objective-C, C++ and Java have been redesigned significantly. As a result the parameters of `-finline-insns`, `--param max-inline-insns-single` and `--param max-inline-insns-auto` need to be reconsidered.
- `--param max-inline-slope` and `--param min-inline-insns` have been removed; they are not needed for the new bottom-up inlining heuristics.
- The new unit-at-a-time compilation scheme has several compatibility issues:
  - The order in which functions, variables, and top-level `asm` statements are emitted may have changed. Code relying on some particular ordering needs to be updated. The majority of such top-level asm statements can be replaced by section attributes.
  - Unreferenced static variables and functions are removed. This may result in undefined references when an `asm` statement refers to the variable/function directly. In that case either the variable/function shall be listed in asm statement operand or in the case of top-level asm statements the attribute `used` shall be used to force function/variable to be always output and considered as a possibly used by unknown code.

    For variables the attribute is accepted only by GCC 3.4 and newer, while for earlier versions it is sufficient to use `unused` to silence warnings about the variables not being referenced. To keep code portable across different GCC versions, you can use appropriate preprocessor conditionals.

  - Static functions now can use non-standard passing conventions that may break `asm` statements calling functions directly. Again the attribute `used` shall be used to prevent this behavior.
  As a temporary workaround, `-fno-unit-at-a-time` can be used, but this scheme may not be supported by future releases of GCC.
- GCC 3.4 automatically places zero-initialized variables in the `.bss` section on some operating systems. Versions of GNU Emacs up to (and including) 21.3 will not work correctly when using this optimization; you can use `-fno-zero-initialized-in-bss` to disable it.
- If GCC 3.4 is configured with `--enable-threads=posix` (the default on most targets that support pthreads) then `_REENTRANT` will be defined unconditionally by some libstdc++ headers. C++ code which relies on that macro to detect whether multi-threaded code is being compiled might change in meaning, possibly resulting in linker errors for single-threaded programs. Affected users of Boost should compile single-threaded code with `-DBOOST_DISABLE_THREADS`. See Bugzilla for more information.

## General Optimizer Improvements

- Usability of the profile feedback and coverage testing has been improved.
  - Performance of profiled programs has been improved by faster profile merging code.
  - Better use of the profile feedback for optimization (loop unrolling and loop peeling).
  - File locking support allowing `fork()` calls and parallel runs of profiled programs.
  - Coverage file format has been redesigned.
  - `gcov` coverage tool has been improved.
  - `make profiledbootstrap` available to build a faster compiler.

    Experiments made on i386 hardware showed an 11% speedup on `-O0` and a 7.5% speedup on `-O2` compilation of a large C++ testcase.

  - New value profiling pass enabled via `-fprofile-values`
  - New value profile transformations pass enabled via `-fvpt` aims to optimize some code sequences by exploiting knowledge about value ranges or other properties of the operands. At the moment a conversion of expensive divisions into cheaper operations has been implemented.
  - New `-fprofile-generate` and `-fprofile-use` command line options to simplify the use of profile feedback.
- A new unit-at-a-time compilation scheme for C, Objective-C, C++ and Java which is enabled via `-funit-at-a-time` (and implied by `-O2`). In this scheme a whole file is parsed first and optimized later. The following basic inter-procedural optimizations are implemented:
  - Removal of unreachable functions and variables
  - Discovery of local functions (functions with static linkage whose address is never taken)
  - On i386, these local functions use register parameter passing conventions.
  - Reordering of functions in topological order of the call graph to enable better propagation of optimizing hints (such as the stack alignments needed by functions) in the back end.
  - Call graph based out-of-order inlining heuristics which allows to limit overall compilation unit growth (`--param inline-unit-growth`).
  Overall, the unit-at-a-time scheme produces a 1.3% improvement for the SPECint2000 benchmark on the i386 architecture (AMD Athlon CPU).
- More realistic code size estimates used by inlining for C, Objective-C, C++ and Java. The growth of large functions can now be limited via `--param large-function-insns` and `--param large-function-growth`.
- A new cfg-level loop optimizer pass replaces the old loop unrolling pass and adds two other loop transformations -- loop peeling and loop unswitching -- and also uses the profile feedback to limit code growth. (The three optimizations are enabled by `-funroll-loops`, `-fpeel-loops` and `-funswitch-loops` flags, respectively).

  The old loop unroller still can be enabled by `-fold-unroll-loops` and may produce better code in some cases, especially when the webizer optimization pass is not run.

- A new web construction pass enabled via `-fweb` (and implied by `-O3`) improves the quality of register allocation, CSE, first scheduling pass and some other optimization passes by avoiding re-use of pseudo registers with non-overlapping live ranges. The pass almost always improves code quality but does make debugging difficult and thus is not enabled by default by `-O2`

  The pass is especially effective as cleanup after code duplication passes, such as the loop unroller or the tracer.

- Experimental implementations of superblock or trace scheduling in the second scheduling pass can be enabled via `-fsched2-use-superblocks` and `-fsched2-use-traces`, respectively.

## New Languages and Language specific improvements

### Ada

- The Ada front end has been updated to include numerous bug fixes and enhancements. These include:
  - Improved project file support
  - Additional set of warnings about potential wrong code
  - Improved error messages
  - Improved code generation
  - Improved cross reference information
  - Improved inlining
  - Better run-time check elimination
  - Better error recovery
  - More efficient implementation of unbounded strings
  - Added features in `GNAT.Sockets`, `GNAT.OS_Lib`, `GNAT.Debug_Pools`, ...
  - New `GNAT.xxxx` packages (e.g. `GNAT.Strings`, `GNAT.Exception_Action`)
  - New pragmas
  - New `-gnatS` switch replacing `gnatpsta`
  - Implementation of new Ada features (in particular limited with, limited aggregates)

### C/Objective-C/C++

- Precompiled headers are now supported. Precompiled headers can dramatically speed up compilation of some projects. There are some known defects in the current precompiled header implementation that will result in compiler crashes in relatively rare situations. Therefore, precompiled headers should be considered a "technology preview" in this release. Read the manual for details about how to use precompiled headers.
- File handling in the preprocessor has been rewritten. GCC no longer gets confused by symlinks and hardlinks, and now has a correct implementation of `#import` and `#pragma once`. These two directives have therefore been un-deprecated.
- The undocumented extension that allowed C programs to have a label at the end of a compound statement, which has been deprecated since GCC 3.0, has been removed.
- The cast-as-lvalue extension has been removed for C++ and deprecated for C and Objective-C. In particular, code like this:

              int i;
              (char) i = 5;

  or this:

              char *p;
              ((int *) p)++;

  is no longer accepted for C++ and will not be accepted for C and Objective-C in a future version.

- The conditional-expression-as-lvalue extension has been deprecated for C and Objective-C. In particular, code like this:

              int a, b, c;
              (a ? b : c) = 2;

  will not be accepted for C and Objective-C in a future version.

- The compound-expression-as-lvalue extension has been deprecated for C and Objective-C. In particular, code like this:

              int a, b;
              (a, b) = 2;

  will not be accepted for C and Objective-C in a future version. A possible non-intrusive workaround is the following:

              (*(a, &b)) = 2;

- Several built-in functions such as `__builtin_popcount` for counting bits, finding the highest and lowest bit in a word, and parity have been added.
- The `-fwritable-strings` option has been deprecated and will be removed.
- Many C math library functions are now recognized as built-ins and optimized.
- The C, C++, and Objective-C compilers can now handle source files written in any character encoding supported by the host C library. The default input character set is taken from the current locale, and may be overridden with the `-finput-charset` command line option. In the future we will add support for inline encoding markers.

### C++

- G++ is now much closer to full conformance to the ISO/ANSI C++ standard. This means, among other things, that a lot of invalid constructs which used to be accepted in previous versions will now be rejected. It is very likely that existing C++ code will need to be fixed. This document lists some of the most common issues.
- A hand-written recursive-descent C++ parser has replaced the YACC-derived C++ parser from previous GCC releases. The new parser contains much improved infrastructure needed for better parsing of C++ source codes, handling of extensions, and clean separation (where possible) between proper semantics analysis and parsing. The new parser fixes many bugs that were found in the old parser.
- You must now use the `typename` and `template` keywords to disambiguate dependent names, as required by the C++ standard.

      	struct K {
      	  typedef int mytype_t;
      	};

      	template <class T1> struct A {
      	  template <class T2> struct B {
      	      void callme(void);
      	    };

      	  template <int N> void bar(void)
      	  {
      	    // Use 'typename' to tell the parser that T1::mytype_t names
      	    //  a type. This is needed because the name is dependent (in
      	    //  this case, on template parameter T1).
      	    typename T1::mytype_t x;
      	    x = 0;
      	  }
      	};

      	template <class T> void template_func(void)
      	{
      	  // Use 'template' to prefix member templates within
      	  //  dependent types (a has type A<T>, which depends on
      	  //  the template parameter T).
      	  A<T> a;
      	  a.template bar<0>();

      	  // Use 'template' to tell the parser that B is a nested
      	  //  template class (dependent on template parameter T), and
      	  //  'typename' because the whole A<T>::B<int> is
      	  //  the name of a type (again, dependent).
      	  typename A<T>::template B<int> b;
      	  b.callme();
      	}

      	void non_template_func(void)
      	{
      	  // Outside of any template class or function, no names can be
      	  //  dependent, so the use of the keyword 'typename' and 'template'
      	  //  is not needed (and actually forbidden).
      	  A<K> a;
      	  a.bar<0>();
      	  A<K>::B<float> b;
      	  b.callme();
      	}

- In a template definition, unqualified names will no longer find members of a dependent base. For example,

      	template <typename T> struct B {
      	  int m;
      	  int n;
      	  int f ();
      	  int g ();
      	};
      	int n;
      	int g ();
      	template <typename T> struct C : B<T> {
      	  void h ()
      	  {
      		m = 0; // error
      		f ();  // error
      		n = 0; // ::n is modified
      		g ();  // ::g is called
      	  }
      	};

  You must make the names dependent, e.g. by prefixing them with `this->`. Here is the corrected definition of `C<T>::h`,

      	template <typename T> void C<T>::h ()
      	{
      	  this->m = 0;
      	  this->f ();
      	  this->n = 0
      	  this->g ();
      	}

  As an alternative solution, you may use `using` declarations instead of `this->`:

      	template <typename T> struct C : B<T> {
      	  using B<T>::m;
      	  using B<T>::f;
      	  using B<T>::n;
      	  using B<T>::g;
      	  void h ()
      	  {
      		m = 0;
      		f ();
      		n = 0;
      		g ();
      	  }
      	};

- In templates, all non-dependent names are now looked up and bound at definition time (while parsing the code), instead of later when the template is instantiated. For instance:

      	void foo(int);

      	template <int> struct A {
      	  static void bar(void){
      	    foo('a');
      	  }
      	};

      	void foo(char);

      	int main()
      	{
      	  A<0>::bar();    // Calls foo(int), used to call foo(char).
      	}

- In an explicit instantiation of a class template, you must use `class` or `struct` before the template-id:

      	template <int N>
      	class A {};

      	template A<0>;         // error, not accepted anymore
      	template class A<0>;   // OK

- The "named return value" and "implicit typename" extensions have been removed.
- Default arguments in function types have been deprecated and will be removed.
- ARM-style name-injection of friend declarations has been deprecated and will be removed. For example: struct S { friend void f(); }; void g() { f(); } will not be accepted by future versions of G++; instead a declaration of "f" will need to be present outside of the scope of "S".
- Covariant returns are implemented for all but varadic functions that require an adjustment.
- When -pedantic is used, G++ now issues errors about spurious semicolons. For example,

              namespace N {}; // Invalid semicolon.
              void f() {}; // Invalid semicolon.

- G++ no longer accepts attributes for a declarator after the initializer associated with that declarator. For example,

              X x(1) __attribute__((...));

  is no longer accepted. Instead, use:

              X x __attribute__((...)) (1);

- Inside the scope of a template class, the name of the class itself can be treated as either a class or a template. So GCC used to accept the class name as argument of type template, and template template parameter. However this is not C++ standard compliant. Now the name is not treated as a valid template template argument unless you qualify the name by its scope. For example, the code below no longer compiles.

              template <template <class> class TT> class X {};
              template <class T> class Y {
                X<Y> x; // Invalid, Y is always a type template parameter.
              };

  The valid code for the above example is

                X< ::Y> x; // Valid.

  (Notice the space between `<` and `:` to prevent GCC to interpret this as a digraph for `[`.)

- Friend declarations that refer to template specializations are rejected if the template has not already been declared. For example,

      	template <typename T>
      	class C {
      	  friend void f<> (C&);
      	};

  is rejected. You must first declare `f` as a template,

      	template <typename T>
      	void f(T);

- In case of friend declarations, every name used in the friend declaration must be accessible at the point of that declaration. Previous versions of G++ used to be less strict about this and allowed friend declarations for `private` class members, for example. See the ISO C++ Standard Committee's defect report #209 for details.
- Declaration of member functions of class templates as friends are supported. For example,

      	template <typename T> struct A {
      	  void f();
      	};
      	class C {
      	  template <typename T> friend void A<T>::f();
      	};

- You must use `template <>` to introduce template specializations, as required by the standard. For example,

      	template <typename T>
      	struct S;

      	struct S<int> { };

  is rejected. You must write,

      	template <> struct S<int> {};

- G++ used to accept code like this,

      	struct S {
      	  int h();
      	  void f(int i = g());
      	  int g(int i = h());
      	};

  This behavior is not mandated by the standard. Now G++ issues an error about this code. To avoid the error, you must move the declaration of `g` before the declaration of `f`. The default arguments for `g` must be visible at the point where it is called.

- The C++ ABI Section 3.3.3 specifications for the array construction routines `__cxa_vec_new2` and `__cxa_vec_new3` were changed to return `NULL` when the allocator argument returns `NULL`. These changes are incorporated into the libstdc++ runtime library.
- Using a name introduced by a typedef in a friend declaration or in an explicit instantiation is now rejected, as specified by the ISO C++ standard.

      	class A;
      	typedef A B;
      	class C {
      	  friend class B;      // error, no typedef name here
      	  friend B;            // error, friend always needs class/struct/enum
      	  friend class A;      // OK
      	};

      	template <int> class Q {};
      	typedef Q<0> R;
      	template class R;      // error, no typedef name here
      	template class Q<0>;   // OK

- When allocating an array with a new expression, GCC used to allow parentheses around the type name. This is actually ill-formed and it is now rejected:

      	int* a = new (int)[10];    // error, not accepted anymore
      	int* a = new int[10];      // OK

- When binding an rvalue of class type to a reference, the copy constructor of the class must be accessible. For instance, consider the following code:

      	class A
      	{
      	public:
      	  A();

      	private:
      	  A(const A&);   // private copy ctor
      	};

      	A makeA(void);
      	void foo(const A&);

      	void bar(void)
      	{
      	  foo(A());       // error, copy ctor is not accessible
      	  foo(makeA());   // error, copy ctor is not accessible

      	  A a1;
      	  foo(a1);        // OK, a1 is a lvalue
      	}

  This might be surprising at first sight, especially since most popular compilers do not correctly implement this rule (further details).

- When forming a pointer to member or a pointer to member function, access checks for class visibility (public, protected, private) are now performed using the qualifying scope of the name itself. This is better explained with an example:

      	class A
      	{
      	public:
      	  void pub_func();
      	protected:
      	  void prot_func();
      	private:
      	  void priv_func();
      	};

      	class B : public A
      	{
      	public:
      	  void foo()
      	  {
      	    &A::pub_func;   // OK, pub_func is accessible through A
      	    &A::prot_func;  // error, cannot access prot_func through A
      	    &A::priv_func;  // error, cannot access priv_func through A

      	    &B::pub_func;   // OK, pub_func is accessible through B
      	    &B::prot_func;  // OK, can access prot_func through B (within B)
      	    &B::priv_func;  // error, cannot access priv_func through B
      	  }
      	};

#### Runtime Library (libstdc++)

- Optimization work:
  - Streamlined `streambuf`, `filebuf`, separate synched with C Standard I/O `streambuf`.
  - All formatted I/O now uses cached locale information.
  - STL optimizations (memory/speed for list, red-black trees as used by sets and maps).
  - More use of GCC builtins.
  - String optimizations (avoid contention on increment/decrement-and-test of the reference count in the empty-string object, constructor from input_iterators speedup).
- Static linkage size reductions.
- Large File Support (files larger than 2 GB on 32-bit systems).
- Wide character and variable encoding `filebuf` work (UTF-8, Unicode).
- Generic character traits.
- Also support `wchar_t` specializations on Mac OS 10.3.x, FreeBSD 5.x, Solaris 2.7 and above, AIX 5.x, Irix 6.5.
- The allocator class is now standard-conformant, and two additional extension allocators have been added, mt_alloc and bitmap_allocator.
- PCH support: -include bits/stdc++.h (2x compile speedup).
- Rewrote `__cxa_demangle` with support for C++ style allocators.
- New debug modes for STL containers and iterators.
- Testsuite rewrite: five times as many tests, plus increasingly sophisticated tests, including I/O, MT, multi-locale, wide and narrow characters.
- Use current versions of GNU "autotools" for build/configuration.

### Objective-C

- The Objective-C front end has been updated to include the numerous bug fixes and enhancements previously available only in Apple's version of GCC. These include:
  - Structured exception (`@try`... `@catch`... `@finally`, `@throw`) and synchronization (`@synchronized`) support. These are accessible via the `-fobjc-exceptions` switch; as of this writing, they may only be used in conjunction with `-fnext-runtime` on Mac OS X 10.3 and later. See Options Controlling Objective-C Dialect for more information.
  - An overhaul of `@encode` logic. The C99 `_Bool` and C++ `bool` type may now be encoded as '`B`'. In addition, the back-end/codegen dependencies have been removed.
  - An overhaul of message dispatch construction, ensuring that the various receiver types (and casts thereof) are handled properly, and that correct diagnostics are issued.
  - Support for "Zero-Link" (`-fzero-link`) and "Fix-and-Continue" (`-freplace-objc-classes`) debugging modes, currently available on Mac OS X 10.3 and later. See Options Controlling Objective-C Dialect for more information.
  - Access to optimized runtime entry points (`-fno-nil-receivers` ) on the assumption that message receivers are never `nil`. This is currently available on Mac OS X 10.3 and later. See Options Controlling Objective-C Dialect for more information.

### Java

- Compiling a .jar file will now cause non-.class entries to be automatically compiled as resources.
- libgcj has been ported to Darwin.
- Jeff Sturm has adapted Jan Hubicka's call graph optimization code to gcj.
- libgcj has a new `gcjlib` URL type; this lets `URLClassLoader` load code from shared libraries.
- libgcj has been much more completely merged with GNU Classpath.
- Class loading is now much more correct; in particular the caller's class loader is now used when that is required.
- Eclipse 2.x will run out of the box using `gij`.
- Parts of `java.nio` have been implemented. Direct and indirect buffers work, as do fundamental file and socket operations.
- `java.awt` has been improved, though it is still not ready for general use.
- The HTTP protocol handler now uses HTTP/1.1 and can handle the POST method.
- The MinGW port has matured. Enhancements include socket timeout support, thread interruption, improved `Runtime.exec()` handling and support for accented characters in filenames.

### Fortran

- Fortran improvements are listed in the Fortran documentation.

## New Targets and Target Specific Improvements

### Alpha

- Several built-in functions have been added such as `__builtin_alpha_zap` to allow utilizing the more obscure instructions of the CPU.
- Parameter passing of complex arguments has changed to match the ABI. This change is incompatible with previous GCC versions, but does fix compatibility with the Tru64 compiler and several corner cases where GCC was incompatible with itself.

### ARM

- Nicolas Pitre has contributed his hand-coded floating-point support code for ARM. It is both significantly smaller and faster than the existing C-based implementation, even when building applications for Thumb. The `arm-elf` configuration has been converted to use the new code.
- Support for the Intel's iWMMXt architecture, a second generation XScale processor, has been added. Enabled at run time with the `-mcpu=iwmmxt` command line switch.
- A new ARM target has been added: `arm-wince-pe`. This is similar to the `arm-pe` target, but it defaults to using the APCS32 ABI.
- The existing ARM pipeline description has been converted to the use the DFA processor pipeline model. There is not much change in code performance, but the description is now easier to understand.
- Support for the Cirrus EP9312 Maverick floating point co-processor added. Enabled at run time with the `-mcpu=ep9312` command line switch. Note however that the multilibs to support this chip are currently disabled in `gcc/config/arm/t-arm-elf`, so if you want to enable their production you will have to uncomment the entries in that file.

### H8/300

- Support for `long long` has been added.
- Support for `saveall` attribute has been added.
- Pavel Pisa contributed hand-written 32-bit-by-32-bit division code for H8/300H and H8S, which is much faster than the previous implementation.
- A lot of small performance improvements.

### IA-32/AMD64 (x86-64)

- Tuning for K8 (AMD Opteron/Athlon64) core is available via `-march=k8` and `-mcpu=k8`.
- Scalar SSE code generation carefully avoids reformatting penalties, hidden dependencies and minimizes the number of uops generated on both Intel and AMD CPUs.
- Vector MMX and SSE operands are now passed in registers to improve performance and match the argument passing convention used by the Intel C++ Compiler. As a result it is not possible to call functions accepting vector arguments compiled by older GCC version.
- Conditional jump elimination is now more aggressive on modern CPUs.
- The Athlon ports has been converted to use the DFA processor pipeline description.
- Optimization of indirect tail calls is now possible in a similar fashion as direct sibcall optimization.
- Further small performance improvements.
- `-m128bit-long-double` is now less buggy.
- `__float128` support in 64-bit compilation.
- Support for data structures exceeding 2GB in 64-bit mode.
- `-mcpu` has been renamed to `-mtune`.

### IA-64

- Tuning code for the Itanium 2 processor has been added. The generation of code tuned for Itanium 2 (option `-mtune=itanium2`) is enabled by default now. To generate code tuned for Itanium 1 the option `-mtune=itanium1` should be used.
- DFA processor pipeline descriptions for the IA-64 processors have been added. This resulted in about 3% improvement on the SPECInt2000 benchmark for Itanium 2.
- Instruction bundling for the IA-64 processors has been rewritten using the DFA pipeline hazard recognizer. It resulted in about 60% compiler speedup on the SPECInt2000 C programs.

### M32R

- Support for the M32R/2 processor has been added by Renesas.
- Support for an M32R Linux target and PIC code generation has been added by Renesas.

### M68000

- Bernardo Innocenti (Develer S.r.l.) has contributed the `m68k-uclinux` target, based on former work done by Paul Dale (SnapGear Inc.). Code generation for the `ColdFire` processors family has been enhanced and extended to support the MCF 53xx and MCF 54xx cores, integrating former work done by Peter Barada (Motorola).

### MIPS

#### Processor-specific changes

- Support for the RM7000 and RM9000 processors has been added. It can be selected using the `-march` compiler option and should work with any MIPS I (`mips-*`) or MIPS III (`mips64-*`) configuration.
- Support for revision 2 of the MIPS32 ISA has been added. It can be selected with the command-line option `-march=mips32r2`.
- There is a new option, `-mfix-sb1`, to work around certain SB-1 errata.

#### Configuration

- It is possible to customize GCC using the following configure-time options:
  - `--with-arch`, which specifies the default value of the `-march` option.
  - `--with-tune`, which specifies the default value of the `-mtune` option.
  - `--with-abi`, which specifies the default ABI.
  - `--with-float=soft`, which tells GCC to use software floating point by default.
  - `--with-float=hard`, which tells GCC to use hardware floating point by default.
- A 64-bit GNU/Linux port has been added. The associated configurations are `mips64-linux-gnu` and `mips64el-linux-gnu`.
- The 32-bit GNU/Linux port now supports Java.
- The IRIX 6 configuration now supports the o32 ABI and will build o32 multilibs by default. This support is compatible with both binutils and the SGI tools, but note that several features, including debugging information and DWARF2 exception handling, are only available when using the GNU assembler. Use of the GNU assembler and linker (version 2.15 or above) is strongly recommended.
- The IRIX 6 configuration now supports 128-bit long doubles.
- There are two new RTEMS-specific configurations, `mips-rtems` and `mipsel-rtems`.
- There are two new `*-elf` configurations, `mipsisa32r2-elf` and `mipsisa32r2el-elf`.

#### General

- Several ABI bugs have been fixed. Unfortunately, these changes will break binary compatibility with earlier releases.
- GCC can now use explicit relocation operators when generating `-mabicalls` code. This behavior is controlled by `-mexplicit-relocs` and can have several performance benefits. For example:
  - It allows for more optimization of GOT accesses, including better scheduling and redundancy elimination.
  - It allows sibling calls to be implemented as jumps.
  - n32 and n64 leaf functions can use a call-clobbered global pointer instead of `$28`.
  - The code to set up `$gp` can be removed from functions that don't need it.
- A new option, `-mxgot`, allows the GOT to be bigger than 64k. This option is equivalent to the assembler's `-xgot` option and should be used instead of `-Wa,-xgot`.
- Frame pointer elimination is now supported when generating 64-bit MIPS16 code.
- Inline block moves have been optimized to take more account of alignment information.
- Many internal changes have been made to the MIPS port, mostly aimed at reducing the reliance on assembler macros.

### PowerPC Darwin

- Support for shared/dylib gcc libraries has been added. It is enabled by default on `powerpc-apple-darwin7.0.0` and up.
- Libgcj is enabled by default. On systems older than `powerpc-apple-darwin7.0.0` you need to install dlcompat.

### S/390 and zSeries

- New command-line options allow to specify the intended execution environment for generated code:
  - `-mesa`/`-mzarch` allows to specify whether to generate code running in ESA/390 mode or in z/Architecture mode (this is applicable to 31-bit code only).
  - `-march` allows to specify a minimum processor architecture level (`g5`, `g6`, `z900`, or `z990`).
  - `-mtune` allows to specify which processor to tune for.
- It is possible to customize GCC using the following configure-time options:
  - `--with-mode`, which specifies whether to default to assuming ESA/390 or z/Architecture mode.
  - `--with-arch`, which specifies the default value of the `-march` option.
  - `--with-tune`, which specifies the default value of the `-mtune` option.
- Support for the z990 processor has been added, and can be selected using `-march=z990` or `-mtune=z990`. This includes instruction scheduling tuned for the superscalar instruction pipeline of the z990 processor as well as support for all new instructions provided by the long-displacement facility.
- Support to generate 31-bit code optimized for zSeries processors (running in ESA/390 or in z/Architecture mode) has been added. This can be selected using `-march=z900` and `-mzarch` respectively.
- Instruction scheduling for the `z900` and `z990` processors now uses the DFA pipeline hazard recognizer.
- GCC no longer generates code to maintain a stack backchain, previously used to generate stack backtraces for debugging purposes. As replacement that does not incur runtime overhead, DWARF-2 call frame information is provided by GCC; this is supported by GDB 6.1. The old behavior can be restored using the `-mbackchain` option.
- The stack frame size of functions may now exceed 2 GB in 64-bit code.
- A port for the 64-bit IBM TPF operating system has been added; the configuration is `s390x-ibm-tpf`. This configuration is supported as cross-compilation target only.
- Various changes to improve the generated code have been implemented, including:
  - GCC now uses the `MULTIPLY AND ADD` and `MULTIPLY AND SUBTRACT` instructions to significantly speed up many floating-point applications.
  - GCC now uses the `ADD LOGICAL WITH CARRY` and `SUBTRACT LOGICAL WITH BORROW` instructions to speed up `long long` arithmetic.
  - GCC now uses the `SEARCH STRING` instruction to implement `strlen()`.
  - In many cases, function call overhead for 31-bit code has been reduced by placing the literal pool after the function code instead of after the function prolog.
  - Register 14 is no longer reserved in 64-bit code.
  - Handling of global register variables has been improved.

### SPARC

- The option `-mflat` is deprecated.
- Support for large (> 2GB) frames has been added to the 64-bit port.
- Several ABI bugs have been fixed. Unfortunately, these changes will break binary compatibility with earlier releases.
- The default debugging format has been switched from STABS to DWARF-2 for 32-bit code on Solaris 7 and later. DWARF-2 is already the default debugging format for 64-bit code on Solaris.

### SuperH

- Support for the SH2E processor has been added. Enabled at run time with the `-m2e` command line switch, or at configure time by specifying sh2e as the machine part of the target triple.

### V850

- Support for the Mitsubishi V850E1 processor has been added. This is a variant of the V850E processor with some additional debugging instructions.

### Xtensa

- Several ABI bugs have been fixed. Unfortunately, these changes break binary compatibility with earlier releases.
  - For big-endian processors, the padding of aggregate return values larger than a word has changed. If the size of an aggregate return value is not a multiple of 32 bits, previous versions of GCC inserted padding in the most-significant bytes of the first return value register. Aggregates larger than a word are now padded in the least-significant bytes of the last return value register used. Aggregates smaller than a word are still padded in the most-significant bytes. The return value padding has not changed for little-endian processors.
  - Function arguments with 16-byte alignment are now properly aligned.
  - The implementation of the `va_list` type has changed. A `va_list` value created by `va_start` from a previous release cannot be used with `va_arg` from this release, or vice versa.
- More processor configuration options for Xtensa processors are supported:
  - the `ABS` instruction is now optional;
  - the `ADDX*` and `SUBX*` instructions are now optional;
  - an experimental `CONST16` instruction can be used to synthesize constants instead of loading them from constant pools.
  These and other Xtensa processor configuration options can no longer be enabled or disabled by command-line options; the processor configuration must be specified by the `xtensa-config.h` header file when building GCC. Additionally, the `-mno-serialize-volatile` option is no longer supported.

## Obsolete Systems

Support for a number of older systems has been declared obsolete in GCC 3.4. Unless there is activity to revive them, the next release of GCC will have their sources permanently removed.

All configurations of the following processor architectures have been declared obsolete:

- Mitsubishi D30V, `d30v-*`
- AT&T DSP1600 and DSP1610, `dsp16xx-*`
- Intel 80960, `i960`

Also, some individual systems have been obsoleted:

- ARM Family
  - Support for generating code for operation in APCS/26 mode (`-mapcs-26`).
- IBM ESA/390
  - "Bigfoot" port, `i370-*`. (The other port, `s390-*`, is actively maintained and supported.)
- Intel 386 family
  - MOSS, `i?86-moss-msdos` and `i?86-*-moss*`
  - NCR 3000 running System V r.4, `i?86-ncr-sysv4*`
  - FreeBSD with a.out object format, `i?86-*-freebsd*aout*` and `i?86-*-freebsd2*`
  - Linux with a.out object format, `i?86-linux*aout*`
  - Linux with libc5, a.k.a. glibc1, `i?86-linux*libc1*`
  - Interix versions before Interix 3, `i?86-*-interix`
  - Mach microkernel, `i?86-mach*`
  - SCO UnixWare with UDK, `i?86-*-udk*`
  - Generic System V releases 1, 2, and 3, `i?86-*-sysv[123]*`
  - VSTa microkernel, `i386-*-vsta`
- Motorola M68000 family
  - HPUX, `m68k-hp-hpux*` and `m68000-hp-hpux*`
  - NetBSD with a.out object format (before NetBSD 1.4), `m68k-*-*-netbsd*` except `m68k-*-*-netbsdelf*`
  - Generic System V r.4, `m68k-*-sysv4*`
- VAX
  - Generic VAX, `vax-*-*` (This is generic VAX only; we have not obsoleted any VAX triples for specific operating systems.)

## Documentation improvements

## Other significant improvements

- The build system has undergone several significant cleanups. Subdirectories will only be configured if they are being built, and all subdirectory configures are run from the `make` command. The top level has been autoconfiscated.
- Building GCC no longer writes to its source directory. This should help those wishing to share a read-only source directory over NFS or build from a CD. The exceptions to this feature are if you configure with either `--enable-maintainer-mode` or `--enable-generated-files-in-srcdir`.
- The `-W` warning option has been renamed to `-Wextra`, which is more easily understood. The older spelling will be retained for backwards compatibility.
- Substantial improvements in compile time have been made, particularly for non-optimizing compilations.

## GCC 3.4.0

### Bug Fixes

A vast number of bugs have been fixed in 3.4.0, too many to publish a complete list here. Follow this link to query the Bugzilla database for the list of over 900 bugs fixed in 3.4.0. This is the list of all bugs marked as resolved and fixed in 3.4.0 that are not flagged as 3.4 regressions.

## GCC 3.4.1

### Bug Fixes

This section lists the problem reports (PRs) from GCC's bug tracking system that are known to be fixed in the 3.4.1 release. This list might not be complete (that is, it is possible that some PRs that have been fixed are not listed here).

#### Bootstrap failures

- 10129 Ada bootstrap fails on PPC-Darwin - invalid assembler emitted - PIC related
- 14576 [ARM] ICE in libiberty when building gcc-3.4 for arm-elf
- 14760 A bug in configure.in prevents using both `--program-suffix` and `--program-prefix`
- 14671 [hppa64] bootstrap fails: ICE in `save_call_clobbered_regs`, in `caller_save.c`
- 15093 [alpha][Java] make bootstrap fails to configure libffi on Alpha
- 15178 Solaris 9/x86 fails linking after stage 3

#### Multi-platform internal compiler errors (ICEs)

- 12753 (preprocessor) Memory corruption in preprocessor on bad input
- 13985 ICE in `gcc.c-torture/compile/930621-1.c`
- 14810 (c++) tree check failures with invalid code involving templates
- 14883 (c++) ICE on invalid code, in cp_parser_lookup_name, in `cp/parser.c`
- 15044 (c++) ICE on syntax error, template header
- 15057 (c++) Compiling of conditional value throw constructs cause a segmentation violation
- 15064 (c++) typeid of template parameter gives ICE
- 15142 (c++) ICE when passing a string where a `char*` is expected in a throw statement
- 15159 ICE in `rtl_verify_flow_info_1`
- 15165 (c++) ICE in `instantiate_template`
- 15193 Unary minus using pointer to V4SF vector causes `-fforce-mem` to exhaust all memory
- 15209 (c++) Runs out of memory with packed structs
- 15227 (c++) Trouble with invalid function definition
- 15285 (c++) instantiate_type ICE when forming pointer to template function
- 15299 (c++) ICE in `resolve_overloaded_unification`
- 15329 (c++) ICE on constructor of member template
- 15550 ICE in `extract_insn`, in `recog.c`
- 15554 (c++) ICE in `tsubst_copy`, in `cp/pt.c`
- 15640 (c++) ICE on invalid code in arg_assoc, in cp/name-`lookup.c`
- 15666 [unit-at-a-time] Gcc abort on valid code
- 15696 (c++) ICE with bad pointer-to-member code
- 15701 (c++) ICE with friends and template template parameter
- 15761 ICE in `do_SUBST`, in `combine.c`
- 15829 (c++) ICE on Botan-1.3.13 due to `-funroll-loops`

#### Ada

- 14538 All RTEMS targets broken for gnat

#### C front end

- 12391 missing warning about assigning to an incomplete type
- 14649 atan(1.0) should not be a constant expression
- 15004 [unit-at-a-time] no warning for unused paramater in static function
- 15749 `--pedantic-errors` behaves differently from `--pedantic` with C-compiler on GNU/Linux

#### C++ compiler and library

- 10646 non-`const` reference is incorrectly matched in a "`const` T" partial specialization
- 12077 `wcin.rdbuf()->in_avail()` return value too high
- 13598 `enc_filebuf` doesn't work
- 14211 `const_cast` returns lvalue but should be rvalue
- 14220 `num_put::do_put()` undesired float/double behavior
- 14245 problem with user-defined allocators in std::basic_string
- 14340 libstdc++ Debug mode: failure to convert iterator to const_iterator
- 14600 `__gnu_cxx::stdio_sync_filebuf` should expose internal `FILE*`
- 14668 no warning anymore for reevaluation of declaration
- 14775 LFS (large file support) tests missing
- 14821 Duplicate namespace alias declaration should not conflict
- 14930 Friend declaration ignored
- 14932 cannot use `offsetof` to get offsets of array elements in g++ 3.4.0
- 14950 [non unit-at-a-time] always_inline does not mix with templates and `-O0`
- 14962 g++ ignores `#pragma redefine_extname`
- 14975 Segfault on low-level write error during imbue
- 15002 Linewise stream input is unusably slow (`std::string` slow)
- 15025 compiler accepts redeclaration of template as non-template
- 15046 [arm] Math functions misdetected by cross configuration
- 15069 a bit test on a variable of `enum` type is miscompiled
- 15074 g++ `-lsupc++` still links against libstdc++
- 15083 spurious "statement has no effect" warning
- 15096 parse error with templates and pointer to `const` member
- 15287 combination of operator[] and operator .* fails in templates
- 15317 `__attribute__` unused in first parameter of constructor gives error
- 15337 `sizeof` on incomplete type diagnostic
- 15361 `bitset<>::_Find_next` fails
- 15412 _GLIBCXX_ symbols symbols defined and used in different namespaces
- 15427 valid code results in incomplete type error
- 15471 Incorrect member pointer offsets in anonymous structs/unions
- 15503 nested template problem
- 15507 compiler hangs while laying out union
- 15542 `operator &` and template definitions
- 15565 SLES9: leading + sign for unsigned `int` with showpos
- 15625 friend defined inside a template fails to find static function
- 15629 Function templates, overloads, and friend name injection
- 15742 'noreturn' attribute ignored in method of template functions.
- 15775 Allocator::pointer consistently ignored
- 15821 Duplicate namespace alias within namespace rejected
- 15862 '`enum yn`' fails (confict with undeclared builtin)
- 15875 rejects pointer to member in template
- 15877 valid code using templates and anonymous enums is rejected
- 15947 Puzzling error message for wrong destructor declaration in template class
- 16020 cannot copy `__gnu_debug::bitset`
- 16154 input iterator concept too restrictive
- 16174 deducing top-level consts

#### Java

- 14315 Java compiler is not parallel make safe

#### Fortran

- 15151 [g77] incorrect logical i/o in 64-bit mode

#### Objective-C

- 7993 private variables cannot be shadowed in subclasses

#### Optimization bugs

- 15228 useless copies of floating point operands
- 15345 [non-unit-at-a-time] unreferenced nested inline functions not optimized away
- 15945 Incorrect floating point optimization
- 15526 ftrapv aborts on 0 * (`-1`)
- 14690 Miscompiled POOMA tests
- 15112 GCC generates code to write to unchanging memory

#### Preprocessor

- 15067 Minor glitch in the source of cpp

#### Main driver program bugs

- 1963 collect2 interprets `-oldstyle_liblookup` as `-o ldstyle_liblookup`

#### x86-specific (Intel/AMD)

- 15717 Error: can't resolve `L0' {*ABS* section} - `xx' {*UND* section}

#### HPPA-specific

- 14782 GCC produces an unaligned data access at `-O2`
- 14828 FAIL: `gcc.c``-torture/execute/20030408-1.c` execution, `-O2`
- 15202 ICE in `reload_cse_simplify_operands`, in `postreload.c`

#### IA64-specific

- 14610 __float80 constants incorrectly emitted
- 14813 init_array sections are initialized in the wrong order
- 14857 GCC segfault on duplicated asm statement
- 15598 Gcc 3.4 ICE on valid code
- 15653 Gcc 3.4 ICE on valid code

#### MIPS-specific

- 15189 wrong filling of delay slot with `-march=mips1 -G0` `-mno-split-addresses` `-mno-explicit-relocs`
- 15331 Assembler error building gnatlib on IRIX 6.5 with GNU as 2.14.91
- 16144 Bogus reference to `__divdf3` when `-O1`
- 16176 Miscompilation of unaligned data in MIPS backend

#### PowerPC-specific

- 11591 ICE in `gcc.dg/altivec-5.c`
- 12028 powerpc-eabispe produces bad sCOND operation
- 14478 rs6000 geu/ltu patterns generate incorrect code
- 14567 long double and va_arg complex args
- 14715 Altivec stack layout may overlap gpr save with stack temps
- 14902 (libstdc++) Stream checking functions fail when `-pthread` option is used.
- 14924 Compiler ICE on valid code
- 14960 `-maltivec` affects vector return with `-mabi=no-altivec`
- 15106 vector varargs failure passing from altivec to non-altivec code for `-m32`
- 16026 ICE in `function`.c:4804, assign_parms, when `-mpowerpc64` & half-word operation
- 15191 `-maltivec` `-mabi=no-altivec` results in mis-aligned lvx and stvx
- 15662 Segmentation fault when an exception is thrown - even if try and catch are specified

#### s390-specific

- 15054 Bad code due to overlapping stack temporaries

#### SPARC-specific

- 15783 ICE with union assignment in 64-bit mode
- 15626 GCC 3.4 emits "ld: warning: relocation error: R_SPARC_UA32"

#### x86-64-specific

- 14326 boehm-gc hardcodes to 3DNow! prefetch for x86_64
- 14723 Backported `-march`=nocona from mainline
- 15290 __float128 failed to pass to function properly

#### Cygwin/Mingw32-specific

- 15250 Option `-mms-bitfields` support on GCC 3.4 is not conformant to MS layout
- 15551 `-mtune=pentium4 -O2` with sjlj EH breaks stack probe worker on windows32 targets

#### Bugs specific to embedded processors

- 8309 [m68k] `-m5200` produces erroneous SImode set of short varaible on stack
- 13250 [SH] Gcc code for rotation clobbers the register, but gcc continues to use the register as if it was not clobbered
- 13803 [coldfire] movqi operand constraints too restrictivefor TARGET_COLDFIRE
- 14093 [SH] ICE for code when using `-mhitachi` option in SH
- 14457 [m6811hc] ICE with simple c++ source
- 14542 [m6811hc] ICE on simple source
- 15100 [SH] cc1plus got hang-up on libstdc++-`v3/testsuite/abi_check.c`c
- 15296 [CRIS] Delayed branch scheduling causing invalid code on cris-*
- 15396 [SH] ICE with `-O2` `-fPIC`
- 15782 [coldfire] m68k_output_mi_thunk emits wrong code for ColdFire

#### Testsuite problems (compiler not affected)

- 11610 libstdc++ testcases 27_io/* don't work properly remotely
- 15488 (libstdc++) possibly insufficient file permissions for executing test suite
- 15489 (libstdc++) testsuite_files determined incorrectly

#### Documentation bugs

- 13928 (libstdc++) no whatis info in some man pages generated by doxygen
- 14150 Ada documentation out of date
- 14949 (c++) Need to document method visibility changes
- 15123 libstdc++`-doc`: Allocators.3 manpage is empty

## GCC 3.4.2

### Bug Fixes

This section lists the problem reports (PRs) from GCC's bug tracking system that are known to be fixed in the 3.4.2 release. This list might not be complete (that is, it is possible that some PRs that have been fixed are not listed here).

#### Bootstrap failures and issues

- 16469 [mips-sgi-irix5.3] bootstrap fails in libstdc++`-v3`/testsuite
- 16344 [hppa-linux-gnu] libstdc++'s PCH built by profiledbootstrap does not work with the built compiler
- 16842 [Solaris/x86] mkheaders can not find `mkheaders.c`onf

#### Multi-platform internal compiler errors (ICEs)

- 12608 (c++) ICE: expected class 't', have 'x' (error_mark) in cp_parser_class_specifier, in `cp/parser.c`
- 14492 ICE in `loc_descriptor_from_tree`, in `dwarf2out.c`
- 15461 (c++) ICE due to NRV and inlining
- 15890 (c++) ICE in `c_expand_expr`, in `c-common.c`
- 16180 ICE: segmentation fault in RTL optimization
- 16224 (c++) ICE in `write_unscoped_name` (template/namespace)
- 16408 ICE: in `delete_insn`, in `cfgrtl.c`
- 16529 (c++) ICE for: namespace-alias shall not be declared as the name of any other entity
- 16698 (c++) ICE with exceptions and declaration of `__cxa_throw`
- 16706 (c++) ICE in `finish_member_declaration`, in `cp/semantics.c`
- 16810 (c++) Legal C++ program with cast gives ICE in `build_ptrmemfunc`
- 16851 (c++) ICE when throwing a comma expression
- 16870 (c++) Boost.Spirit causes ICE in `tsubst`, in `cp/pt.c`
- 16904 (c++) ICE in `finish_class_member_access_expr`, in `cp/typeck.c`
- 16905 (c++) ICE (segfault) with exceptions
- 16964 (c++) ICE in `cp_parser_class_specifier` due to redefinition
- 17068 (c++) ICE: tree check: expected class 'd', have 'x' (identifier_node) in `dependent_template_p`, in `cp/pt.c`

#### Preprocessor bugs

- 16366 Preprocessor option `-remap` causes memory corruption

#### Optimization

- 15345 unreferenced nested inline functions not optimized away
- 16590 Incorrect execution when compiling with `-O2`
- 16693 Bitwise AND is lost when used within a cast to an `enum` of the same precision
- 17078 Jump into `if(0)` substatement fails

#### Problems in generated debug information

- 13956 incorrect stabs for nested local variables

#### C front end bugs

- 16684 GCC should not warn about redundant redeclarations of built-ins

#### C++ compiler and library

- 12658 Thread safety problems in `locale::global()` and `locale::locale()`
- 13092 g++ accepts invalid pointer-to-member conversion
- 15320 Excessive memory consumption
- 16246 Incorrect template argument deduction
- 16273 Memory exhausted when using nested classes and virtual functions
- 16401 `ostringstream` in gcc 3.4.x very slow for big data
- 16411 undefined reference to `__gnu_cxx::stdio_sync_filebuf<char, std::char_traits<char> >::file()`
- 16489 G++ incorrectly rejects use of a null constant integral expression as a null constant pointer
- 16618 `offsetof` fails with constant member
- 16637 syntax error reported for valid input code
- 16717 `__attribute__((constructor))` broken in C++
- 16813 compiler error in DEBUG version of range insertion `std::map::insert`
- 16853 pointer-to-member initialization from incompatible one accepted
- 16889 ambiguity is not detected
- 16959 Segmentation fault in `ios_base::sync_with_stdio`

#### Java compiler and library

- 7587 direct threaded interpreter not thread-safe
- 16473 ServerSocket `accept()` leaks file descriptors
- 16478 Hash synchronization deadlock with finalizers

#### Alpha-specific

- 10695 ICE in `dwarf2out_frame_debug_expr`, in `dwarf2out.c`
- 16974 could not split insn (ice in `final_scan_insn`, in `final.c`)

#### x86-specific

- 16298 ICE in `output_operand`
- 17113 ICE with SSE2 intrinsics

#### x86-64 specific

- 14697 libstdc++ couldn't find 32bit libgcc_s

#### MIPS-specific

- 15869 [mips64] No NOP after LW (with `-mips1` `-O0`)
- 16325 [mips64] value profiling clobbers gp on mips
- 16357 [mipsisa64-elf] ICE copying 7 bytes between extern char[]s
- 16380 [mips64] Use of uninitialised register after dbra conversion
- 16407 [mips64] Unaligned access to local variables
- 16643 [mips64] verify_local_live_at_start ICE after crossjumping & cfgcleanup

#### ARM-specific

- 15927 THUMB `-O2`: strength-reduced iteration variable ends up off by 1
- 15948 THUMB: ICE with non-commutative cbranch
- 17019 THUMB: bad switch statement in md code for addsi3_cbranch_scratch

#### IA64-specific

- 16130 ICE on valid code: in bundling, in `config/ia64/ia64.c` (`-mtune=merced`)
- 16142 ICE on valid code: in bundling, in `config/ia64/ia64.c` (`-mtune=itanium`)
- 16278 Gcc failed to build Linux kernel with `-mtune=merced`
- 16414 ICE on valid code: typo in comparison of `asm_noperands` result
- 16445 ICE on valid code: don't count ignored insns
- 16490 ICE (segfault) while compiling with `-fprofile-use`
- 16683 ia64 does not honor SUBTARGET_EXTRA_SPECS

#### PowerPC-specific

- 16195 (ppc64): Miscompilation of GCC 3.3.x by 3.4.x
- 16239 ICE on ppc64 (mozilla 1.7 compile, `-O1` `-fno-exceptions` issue)

#### SPARC-specific

- 16199 ICE while compiling apache 2.0.49
- 16416 `-m64` doesn't imply `-mcpu=v9` anymore
- 16430 ICE when returning non-C aggregates larger than 16 bytes

#### Bugs specific to embedded processors

- 16379 [m32r] can't output large model function call of `memcpy`
- 17093 [m32r] ICE with `-msdata=use` `-O0`
- 17119 [m32r] ICE at switch case 0x8000

#### DJGPP-specific

- 15928 libstdc++ in 3.4.x doesn't cross-compile for djgpp

#### Alpha Tru64-specific

- 16210 libstdc++ gratuitously omits "`long long`" I/O

#### Testsuite, documentation issues (compiler is not affected):

- 15488 (libstdc++) possibly insufficient file permissions for executing test suite
- 16250 ada/doctools runs makeinfo even in release tarball

## GCC 3.4.3

This is the list of problem reports (PRs) from GCC's bug tracking system that are known to be fixed in the 3.4.3 release. This list might not be complete (that is, it is possible that some PRs that have been fixed are not listed here).

#### Bootstrap failures

- 17369 [ia64] Bootstrap failure with binutils-2.15.90.0.1.1
- 17850 [arm-elf] bootstrap failure - libstdc++ uses strtold when undeclared

#### Internal compiler errors (ICEs) affecting multiple platforms

- 13948 (java) GCJ segmentation fault while compiling GL4Java .class files
- 14492 ICE in `loc_descriptor_from_tree`, in `dwarf2out.c`
- 16301 (c++) ICE when "strong" attribute is attached to a `using` directive
- 16566 ICE with flexible arrays
- 17023 ICE with nested functions in parameter declaration
- 17027 ICE with noreturn function in loop at `-O2`
- 17524 ICE in `grokdeclarator`, in `cp/decl.c`
- 17826 (c++) ICE in `cp_tree_equal`

#### C and optimization bugs

- 15526 `-ftrapv` aborts on `0 * (-1)`
- 16999 `#ident` stopped working
- 17503 quadratic behaviour in invalid_mode_change_p
- 17581 Long long arithmetic fails inside a switch/case statement when compiled with `-O2`
- 18129 `-fwritable-strings` doesn't work

#### C++ compiler and library bugs

- 10975 incorrect initial `ostringstream::tellp()`
- 11722 Unbuffered `filebuf::sgetn` is slow
- 14534 Unrecognizing static function as a template parameter when its return value is also templated
- 15172 Copy constructor optimization in aggregate initialization
- 15786 Bad error message for frequently occuring error.
- 16162 Rejects valid member-template-definition
- 16612 empty basic_strings can't live in shared memory
- 16715 `std::basic_iostream` is instantiated when used, even though instantiations are already contained in libstdc++
- 16848 code in `/ext/demangle.h` appears broken
- 17132 GCC fails to eliminate function template specialization when argument deduction fails
- 17259 One more `_S_leaf` incorrectly qualified with `_RopeRep::` in `ropeimpl.h`
- 17327 use of `enumeral_type' in template type unification
- 17393 "unused variable '._0'" warning with `-Wall`
- 17501 Confusion with member templates
- 17537 g++ not passing `-lstdc`++ to linker when all command line arguments are libraries
- 17585 usage of unqualified name of static member from within class not allowed
- 17821 Poor diagnostic for using "." instead of "->"
- 17829 wrong error: call of overloaded function is ambiguous
- 17851 Misleading diagnostic for invalid function declarations with undeclared types
- 17976 Destructor is called twice
- 18020 rejects valid definition of `enum` value in template
- 18093 bogus conflict in namespace aliasing
- 18140 C++ parser bug when using >> in templates

#### Fortran

- 17541 data statements with double precision constants fail

#### x86-specific

- 17853 `-O2` ICE for MMX testcase

#### Sparc-specific

- 17245 ICE compiling gsl-1.5 `statistics/lag1.c`

#### Darwin-specific

- 17167 FATAL:Symbol `L_foo$stub` already defined.

#### AIX-specific

- 17277 could not catch an exception when specified `-maix64`

#### Solaris-specific

- 17505 `<cmath>` calls `acosf()`, `ceilf()`, and other functions missing from system libraries

#### HP/UX specific:

- 17684 /usr/ccs/bin/ld: Can't create `libgcc_s.sl`

#### ARM-specific

- 17384 ICE with mode attribute on structures

#### MIPS-specific

- 17770 No NOP after LWL with `-mips1`

#### Other embedded target specific

- 11476 [arc-elf] gcc ICE on newlib's `vfprintf.c`
- 14064 [avr-elf] `-fdata-sections` triggers ICE
- 14678 [m68hc11-elf] gcc ICE
- 15583 [powerpc-rtems] powerpc-rtems lacks `__USE_INIT_FINI__`
- 15790 [i686-coff] Alignment error building gcc with i686-coff target
- 15886 [SH] Miscompilation with `-O2` `-fPIC`
- 16884 [avr-elf] [fweb related] bug while initializing variables

#### Bugs relating to debugger support

- 13841 missing debug info for `_Complex` function arguments
- 15860 [big-endian targets] No `DW_AT_location` debug info is emitted for formal arguments to a function that uses "register" qualifiers

#### Testsuite issues (compiler not affected)

- 17465 Testsuite in libffi overrides LD_LIBRARY_PATH
- 17469 Testsuite in libstdc++ overrides LD_LIBRARY_PATH
- 18138 [mips-sgi-irix6.5] `libgcc_s.so.1` not found by 64-bit testsuite

#### Documentation

- 15498 typo in gcc manual: non-existing locale example en_UK, should be en_GB
- 15747 [mips-sgi-irix5.3] /bin/sh hangs during bootstrap: document broken shell
- 16406 USE_LD_AS_NEEDED undocumented

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Last modified 2004-11-09 |