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Diffstat (limited to 'gcc-4.2.1-5666.3/gcc/cp/NEWS')
| -rw-r--r-- | gcc-4.2.1-5666.3/gcc/cp/NEWS | 401 |
1 files changed, 0 insertions, 401 deletions
diff --git a/gcc-4.2.1-5666.3/gcc/cp/NEWS b/gcc-4.2.1-5666.3/gcc/cp/NEWS deleted file mode 100644 index 6825b9e3c..000000000 --- a/gcc-4.2.1-5666.3/gcc/cp/NEWS +++ /dev/null @@ -1,401 +0,0 @@ -*** Changes in GCC 3.4: - -* Changes in GCC 3.4 are described in 'gcc-3.4/changes.html' - -*** Changes in GCC 3.3: - -* The "new X = 3" extension has been removed; you must now use "new X(3)". - -* G++ no longer allows in-class initializations of static data members - that do not have arithmetic or enumeration type. For example: - - struct S { - static const char* const p = "abc"; - }; - - is no longer accepted. - - Use the standards-conformant form: - - struct S { - static const char* const p; - }; - - const char* const S::p = "abc"; - - instead. - - (ISO C++ is even stricter; it does not allow in-class - initializations of floating-point types.) - -*** Changes in GCC 3.1: - -* -fhonor-std and -fno-honor-std have been removed. -fno-honor-std was - a workaround to allow std compliant code to work with the non-std - compliant libstdc++-v2. libstdc++-v3 is std compliant. - -* The C++ ABI has been fixed so that `void (A::*)() const' is mangled as - "M1AKFvvE", rather than "MK1AFvvE" as before. This change only affects - pointer to cv-qualified member function types. - -* The C++ ABI has been changed to correctly handle this code: - - struct A { - void operator delete[] (void *, size_t); - }; - - struct B : public A { - }; - - new B[10]; - - The amount of storage allocated for the array will be greater than - it was in 3.0, in order to store the number of elements in the - array, so that the correct size can be passed to `operator delete[]' - when the array is deleted. Previously, the value passed to - `operator delete[]' was unpredictable. - - This change will only affect code that declares a two-argument - `operator delete[]' with a second parameter of type `size_t' - in a base class, and does not override that definition in a - derived class. - -* The C++ ABI has been changed so that: - - struct A { - void operator delete[] (void *, size_t); - void operator delete[] (void *); - }; - - does not cause unnecessary storage to be allocated when an array of - `A' objects is allocated. - - This change will only affect code that declares both of these - forms of `operator delete[]', and declared the two-argument form - before the one-argument form. - -* The C++ ABI has been changed so that when a parameter is passed by value, - any cleanup for that parameter is performed in the caller, as specified - by the ia64 C++ ABI, rather than the called function as before. As a - result, classes with a non-trivial destructor but a trivial copy - constructor will be passed and returned by invisible reference, rather - than by bitwise copy as before. - -* G++ now supports the "named return value optimization": for code like - - A f () { - A a; - ... - return a; - } - - G++ will allocate 'a' in the return value slot, so that the return - becomes a no-op. For this to work, all return statements in the function - must return the same variable. - -*** Changes in GCC 3.0: - -* Support for guiding declarations has been removed. - -* G++ now supports importing member functions from base classes with a - using-declaration. - -* G++ now enforces access control for nested types. - -* In some obscure cases, functions with the same type could have the - same mangled name. This bug caused compiler crashes, link-time clashes, - and debugger crashes. Fixing this bug required breaking ABI - compatibility for the functions involved. The functions in questions - are those whose types involve non-type template arguments whose - mangled representations require more than one digit. - -* Support for assignment to `this' has been removed. This idiom - was used in the very early days of C++, before users were allowed - to overload `operator new'; it is no longer allowed by the C++ - standard. - -* Support for signatures, a G++ extension, have been removed. - -* Certain invalid conversions that were previously accepted will now - be rejected. For example, assigning function pointers of one type - to function pointers of another type now requires a cast, whereas - previously g++ would sometimes accept the code even without the - cast. - -* G++ previously allowed `sizeof (X::Y)' where Y was a non-static - member of X, even if the `sizeof' expression occurred outside - of a non-static member function of X (or one of its derived classes, - or a member-initializer for X or one of its derived classes.) This - extension has been removed. - -* G++ no longer allows you to overload the conditional operator (i.e., - the `?:' operator.) - -* The "named return value" extension: - - int f () return r { r = 3; } - - has been deprecated, and will be removed in a future version of G++. - -*** Changes in GCC 2.95: - -* Messages about non-conformant code that we can still handle ("pedwarns") - are now errors by default, rather than warnings. This can be reverted - with -fpermissive, and is overridden by -pedantic or -pedantic-errors. - -* String constants are now of type `const char[n]', rather than `char[n]'. - This can be reverted with -fno-const-strings. - -* References to functions are now supported. - -* Lookup of class members during class definition now works in all cases. - -* In overload resolution, type conversion operators are now properly - treated as always coming from the most derived class. - -* C9x-style restricted pointers are supported, using the `__restrict' - keyword. - -* You can now use -fno-implicit-inline-templates to suppress writing out - implicit instantiations of inline templates. Normally we do write them - out, even with -fno-implicit-templates, so that optimization doesn't - affect which instantiations are needed. - -* -fstrict-prototype now also suppresses implicit declarations. - -* Many obsolete options have been removed: -fall-virtual, -fmemoize-lookups, - -fsave-memoized, +e?, -fenum-int-equivalence, -fno-nonnull-objects. - -* Unused virtual functions can be discarded on some targets by specifying - -ffunction-sections -fvtable-gc to the compiler and --gc-sections to the - linker. Unfortunately, this only works on Linux if you're linking - statically. - -* Lots of bugs stomped. - -*** Changes in EGCS 1.1: - -* Namespaces are fully supported. The library has not yet been converted - to use namespace std, however, and the old std-faking code is still on by - default. To turn it off, you can use -fhonor-std. - -* Massive template improvements: - + member template classes are supported. - + template friends are supported. - + template template parameters are supported. - + local classes in templates are supported. - + lots of bugs fixed. - -* operator new now throws bad_alloc where appropriate. - -* Exception handling is now thread safe, and supports nested exceptions and - placement delete. Exception handling overhead on x86 is much lower with - GNU as 2.9. - -* protected virtual inheritance is now supported. - -* Loops are optimized better; we now move the test to the end in most - cases, like the C frontend does. - -* For class D derived from B which has a member 'int i', &D::i is now of - type 'int B::*' instead of 'int D::*'. - -* An _experimental_ new ABI for g++ can be turned on with -fnew-abi. The - current features of this are more efficient allocation of base classes - (including the empty base optimization), and more compact mangling of C++ - symbol names (which can be turned on separately with -fsquangle). This - ABI is subject to change without notice, so don't use it for anything - that you don't want to rebuild with every release of the compiler. - - As with all ABI-changing flags, this flag is for experts only, as all - code (including the library code in libgcc and libstdc++) must be - compiled with the same ABI. - -*** Changes in EGCS 1.0: - -* A public review copy of the December 1996 Draft of the ISO/ANSI C++ - standard is now available. See - - http://www.cygnus.com/misc/wp/ - - for more information. - -* g++ now uses a new implementation of templates. The basic idea is that - now templates are minimally parsed when seen and then expanded later. - This allows conformant early name binding and instantiation controls, - since instantiations no longer have to go through the parser. - - What you get: - - + Inlining of template functions works without any extra effort or - modifications. - + Instantiations of class templates and methods defined in the class - body are deferred until they are actually needed (unless - -fexternal-templates is specified). - + Nested types in class templates work. - + Static data member templates work. - + Member function templates are now supported. - + Partial specialization of class templates is now supported. - + Explicit specification of template parameters to function templates - is now supported. - - Things you may need to fix in your code: - - + Syntax errors in templates that are never instantiated will now be - diagnosed. - + Types and class templates used in templates must be declared - first, or the compiler will assume they are not types, and fail. - + Similarly, nested types of template type parameters must be tagged - with the 'typename' keyword, except in base lists. In many cases, - but not all, the compiler will tell you where you need to add - 'typename'. For more information, see - - http://www.cygnus.com/misc/wp/dec96pub/template.html#temp.res - - + Guiding declarations are no longer supported. Function declarations, - including friend declarations, do not refer to template instantiations. - You can restore the old behavior with -fguiding-decls until you fix - your code. - - Other features: - - + Default function arguments in templates will not be evaluated (or - checked for semantic validity) unless they are needed. Default - arguments in class bodies will not be parsed until the class - definition is complete. - + The -ftemplate-depth-NN flag can be used to increase the maximum - recursive template instantiation depth, which defaults to 17. If you - need to use this flag, the compiler will tell you. - + Explicit instantiation of template constructors and destructors is - now supported. For instance: - - template A<int>::A(const A&); - - Still not supported: - - + Member class templates. - + Template friends. - -* Exception handling support has been significantly improved and is on by - default. The compiler supports two mechanisms for walking back up the - call stack; one relies on static information about how registers are - saved, and causes no runtime overhead for code that does not throw - exceptions. The other mechanism uses setjmp and longjmp equivalents, and - can result in quite a bit of runtime overhead. You can determine which - mechanism is the default for your target by compiling a testcase that - uses exceptions and doing an 'nm' on the object file; if it uses __throw, - it's using the first mechanism. If it uses __sjthrow, it's using the - second. - - You can turn EH support off with -fno-exceptions. - -* RTTI support has been rewritten to work properly and is now on by default. - This means code that uses virtual functions will have a modest space - overhead. You can use the -fno-rtti flag to disable RTTI support. - -* On ELF systems, duplicate copies of symbols with 'initialized common' - linkage (such as template instantiations, vtables, and extern inlines) - will now be discarded by the GNU linker, so you don't need to use -frepo. - This support requires GNU ld from binutils 2.8 or later. - -* The overload resolution code has been rewritten to conform to the latest - C++ Working Paper. Built-in operators are now considered as candidates - in operator overload resolution. Function template overloading chooses - the more specialized template, and handles base classes in type deduction - and guiding declarations properly. In this release the old code can - still be selected with -fno-ansi-overloading, although this is not - supported and will be removed in a future release. - -* Standard usage syntax for the std namespace is supported; std is treated - as an alias for global scope. General namespaces are still not supported. - -* New flags: - - + New warning -Wno-pmf-conversion (don't warn about - converting from a bound member function pointer to function - pointer). - - + A flag -Weffc++ has been added for violations of some of the style - guidelines in Scott Meyers' _Effective C++_ books. - - + -Woverloaded-virtual now warns if a virtual function in a base - class is hidden in a derived class, rather than warning about - virtual functions being overloaded (even if all of the inherited - signatures are overridden) as it did before. - - + -Wall no longer implies -W. The new warning flag, -Wsign-compare, - included in -Wall, warns about dangerous comparisons of signed and - unsigned values. Only the flag is new; it was previously part of - -W. - - + The new flag, -fno-weak, disables the use of weak symbols. - -* Synthesized methods are now emitted in any translation units that need - an out-of-line copy. They are no longer affected by #pragma interface - or #pragma implementation. - -* __FUNCTION__ and __PRETTY_FUNCTION__ are now treated as variables by the - parser; previously they were treated as string constants. So code like - `printf (__FUNCTION__ ": foo")' must be rewritten to - `printf ("%s: foo", __FUNCTION__)'. This is necessary for templates. - -* local static variables in extern inline functions will be shared between - translation units. - -* -fvtable-thunks is supported for all targets, and is the default for - Linux with glibc 2.x (also called libc 6.x). - -* bool is now always the same size as another built-in type. Previously, - a 64-bit RISC target using a 32-bit ABI would have 32-bit pointers and a - 64-bit bool. This should only affect Irix 6, which was not supported in - 2.7.2. - -* new (nothrow) is now supported. - -* Synthesized destructors are no longer made virtual just because the class - already has virtual functions, only if they override a virtual destructor - in a base class. The compiler will warn if this affects your code. - -* The g++ driver now only links against libstdc++, not libg++; it is - functionally identical to the c++ driver. - -* (void *)0 is no longer considered a null pointer constant; NULL in - <stddef.h> is now defined as __null, a magic constant of type (void *) - normally, or (size_t) with -ansi. - -* The name of a class is now implicitly declared in its own scope; A::A - refers to A. - -* Local classes are now supported. - -* __attribute__ can now be attached to types as well as declarations. - -* The compiler no longer emits a warning if an ellipsis is used as a - function's argument list. - -* Definition of nested types outside of their containing class is now - supported. For instance: - - struct A { - struct B; - B* bp; - }; - - struct A::B { - int member; - }; - -* On the HPPA, some classes that do not define a copy constructor - will be passed and returned in memory again so that functions - returning those types can be inlined. - -*** The g++ team thanks everyone that contributed to this release, - but especially: - -* Joe Buck <jbuck@synopsys.com>, the maintainer of the g++ FAQ. -* Brendan Kehoe <brendan@cygnus.com>, who coordinates testing of g++. -* Jason Merrill <jason@cygnus.com>, the g++ maintainer. -* Mark Mitchell <mmitchell@usa.net>, who implemented member function - templates and explicit qualification of function templates. -* Mike Stump <mrs@wrs.com>, the previous g++ maintainer, who did most of - the exception handling work. |