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diff --git a/contrib/gcc/cp/gpcompare.texi b/contrib/gcc/cp/gpcompare.texi deleted file mode 100644 index 7b0d573..0000000 --- a/contrib/gcc/cp/gpcompare.texi +++ /dev/null @@ -1,236 +0,0 @@ -@node ANSI -@chapter @sc{gnu} C++ Conformance to @sc{ansi} C++ - -These changes in the @sc{gnu} C++ compiler were made to comply more -closely with the @sc{ansi} base document, @cite{The Annotated C++ -Reference Manual} (the @sc{arm}). Further reducing the divergences from -@sc{ansi} C++ is a continued goal of the @sc{gnu} C++ Renovation -Project. - -@b{Section 3.4}, @i{Start and Termination}. It is now invalid to take -the address of the function @samp{main()}. - -@b{Section 4.8}, @i{Pointers to Members}. The compiler produces -an error for trying to convert between a pointer to a member and the type -@samp{void *}. - -@b{Section 5.2.5}, @i{Increment and Decrement}. It is an error to use -the increment and decrement operators on an enumerated type. - -@b{Section 5.3.2}, @i{Sizeof}. Doing @code{sizeof} on a function is now -an error. - -@b{Section 5.3.4}, @i{Delete}. The syntax of a @i{cast-expression} is -now more strictly controlled. - -@b{Section 7.1.1}, @i{Storage Class Specifiers}. Using the -@code{static} and @code{extern} specifiers can now only be applied to -names of objects, functions, and anonymous unions. - -@b{Section 7.1.1}, @i{Storage Class Specifiers}. The compiler no longer complains -about taking the address of a variable which has been declared to have @code{register} -storage. - -@b{Section 7.1.2}, @i{Function Specifiers}. The compiler produces an -error when the @code{inline} or @code{virtual} specifiers are -used on anything other than a function. - -@b{Section 8.3}, @i{Function Definitions}. It is now an error to shadow -a parameter name with a local variable; in the past, the compiler only -gave a warning in such a situation. - -@b{Section 8.4.1}, @i{Aggregates}. The rules concerning declaration of -an aggregate are now all checked in the @sc{gnu} C++ compiler; they -include having no private or protected members and no base classes. - -@b{Section 8.4.3}, @i{References}. Declaring an array of references is -now forbidden. Initializing a reference with an initializer list is -also considered an error. - -@b{Section 9.5}, @i{Unions}. Global anonymous unions must be declared -@code{static}. - -@b{Section 11.4}, @i{Friends}. Declaring a member to be a friend of a -type that has not yet been defined is an error. - -@b{Section 12.1}, @i{Constructors}. The compiler generates a -default copy constructor for a class if no constructor has been declared. - -@ignore -@b{Section 12.4}, @i{Destructors}. In accordance with the @sc{ansi} C++ -draft standard working paper, a pure virtual destructor must now be -defined. -@end ignore - -@b{Section 12.6.2}, @i{Special Member Functions}. When using a -@i{mem-initializer} list, the compiler will now initialize class members -in declaration order, not in the order in which you specify them. -Also, the compiler enforces the rule that non-static @code{const} -and reference members must be initialized with a @i{mem-initializer} -list when their class does not have a constructor. - -@b{Section 12.8}, @i{Copying Class Objects}. The compiler generates -default copy constructors correctly, and supplies default assignment -operators compatible with user-defined ones. - -@b{Section 13.4}, @i{Overloaded Operators}. An overloaded operator may -no longer have default arguments. - -@b{Section 13.4.4}, @i{Function Call}. An overloaded @samp{operator ()} -must be a non-static member function. - -@b{Section 13.4.5}, @i{Subscripting}. An overloaded @samp{operator []} -must be a non-static member function. - -@b{Section 13.4.6}, @i{Class Member Access}. An overloaded @samp{operator ->} -must be a non-static member function. - -@b{Section 13.4.7}, @i{Increment and Decrement}. The compiler will now -make sure a postfix @samp{@w{operator ++}} or @samp{@w{operator --}} has an -@code{int} as its second argument. - - -@node Encoding -@chapter Name Encoding in @sc{gnu} C++ - -@c FIXME!! rewrite name encoding section -@c ...to give complete rules rather than diffs from ARM. -@c To avoid plagiarism, invent some different way of structuring the -@c description of the rules than what ARM uses. - -@cindex mangling -@cindex name encoding -@cindex encoding information in names -In order to support its strong typing rules and the ability to provide -function overloading, the C++ programming language @dfn{encodes} -information about functions and objects, so that conflicts across object -files can be detected during linking. @footnote{This encoding is also -sometimes called, whimsically enough, @dfn{mangling}; the corresponding -decoding is sometimes called @dfn{demangling}.} These rules tend to be -unique to each individual implementation of C++. - -The scheme detailed in the commentary for 7.2.1 of @cite{The Annotated -Reference Manual} offers a description of a possible implementation -which happens to closely resemble the @code{cfront} compiler. The -design used in @sc{gnu} C++ differs from this model in a number of ways: - -@itemize @bullet -@item -In addition to the basic types @code{void}, @code{char}, @code{short}, -@code{int}, @code{long}, @code{float}, @code{double}, and @code{long -double}, @sc{gnu} C++ supports two additional types: @code{wchar_t}, the wide -character type, and @code{long long} (if the host supports it). The -encodings for these are @samp{w} and @samp{x} respectively. - -@item -According to the @sc{arm}, qualified names (e.g., @samp{foo::bar::baz}) are -encoded with a leading @samp{Q}. Followed by the number of -qualifications (in this case, three) and the respective names, this -might be encoded as @samp{Q33foo3bar3baz}. @sc{gnu} C++ adds a leading -underscore to the list, producing @samp{_Q33foo3bar3baz}. - -@item -The operator @samp{*=} is encoded as @samp{__aml}, not @samp{__amu}, to -match the normal @samp{*} operator, which is encoded as @samp{__ml}. - -@c XXX left out ->(), __wr -@item -In addition to the normal operators, @sc{gnu} C++ also offers the minimum and -maximum operators @samp{>?} and @samp{<?}, encoded as @samp{__mx} and -@samp{__mn}, and the conditional operator @samp{?:}, encoded as @samp{__cn}. - -@cindex destructors, encoding of -@cindex constructors, encoding of -@item -Constructors are encoded as simply @samp{__@var{name}}, where @var{name} -is the encoded name (e.g., @code{3foo} for the @code{foo} class -constructor). Destructors are encoded as two leading underscores -separated by either a period or a dollar sign, depending on the -capabilities of the local host, followed by the encoded name. For -example, the destructor @samp{foo::~foo} is encoded as @samp{_$_3foo}. - -@item -Virtual tables are encoded with a prefix of @samp{_vt}, rather than -@samp{__vtbl}. The names of their classes are separated by dollar signs -(or periods), and not encoded as normal: the virtual table for -@code{foo} is @samp{__vt$foo}, and the table for @code{foo::bar} is -named @samp{__vt$foo$bar}. - -@item -Static members are encoded as a leading underscore, followed by the -encoded name of the class in which they appear, a separating dollar sign -or period, and finally the unencoded name of the variable. For example, -if the class @code{foo} contains a static member @samp{bar}, its -encoding would be @samp{_3foo$bar}. - -@item -@sc{gnu} C++ is not as aggressive as other compilers when it comes to always -generating @samp{Fv} for functions with no arguments. In particular, -the compiler does not add the sequence to conversion operators. The -function @samp{foo::bar()} is encoded as @samp{bar__3foo}, not -@samp{bar__3fooFv}. - -@item -The argument list for methods is not prefixed by a leading @samp{F}; it -is considered implied. - -@item -@sc{gnu} C++ approaches the task of saving space in encodings -differently from that noted in the @sc{arm}. It does use the -@samp{T@var{n}} and @samp{N@var{x}@var{y}} codes to signify copying the -@var{n}th argument's type, and making the next @var{x} arguments be the -type of the @var{y}th argument, respectively. However, the values for -@var{n} and @var{y} begin at zero with @sc{gnu} C++, whereas the -@sc{arm} describes them as starting at one. For the function @samp{foo -(bartype, bartype)}, @sc{gnu} C++ uses @samp{foo__7bartypeT0}, while -compilers following the @sc{arm} example generate @samp{foo__7bartypeT1}. - -@c Note it loses on `foo (int, int, int, int, int)'. -@item -@sc{gnu} C++ does not bother using the space-saving methods for types whose -encoding is a single character (like an integer, encoded as @samp{i}). -This is useful in the most common cases (two @code{int}s would result in -using three letters, instead of just @samp{ii}). -@end itemize - -@c @node Cfront -@c @chapter @code{cfront} Compared to @sc{gnu} C++ -@c -@c -@c FIXME!! Fill in. Consider points in the following: -@c -@c @display -@c Date: Thu, 2 Jan 92 21:35:20 EST -@c From: raeburn@@cygnus.com -@c Message-Id: <9201030235.AA10999@@cambridge.cygnus.com> -@c To: mrs@@charlie.secs.csun.edu -@c Cc: g++@@cygnus.com -@c Subject: Re: ARM and GNU C++ incompatabilities -@c -@c Along with that, we should probably describe how g++ differs from -@c cfront, in ways that the users will notice. (E.g., cfront supposedly -@c allows "free (new char[10])"; does g++? How do the template -@c implementations differ? "New" placement syntax?) -@c @end display -@c -@c XXX For next revision. -@c -@c GNU C++: -@c * supports expanding inline functions in many situations, -@c including those which have static objects, use `for' statements, -@c and other situations. Part of this versatility is due to is -@c ability to not always generate temporaries for assignments. -@c * deliberately allows divide by 0 and mod 0, since [according -@c to Wilson] there are actually situations where you'd like to allow -@c such things. Note on most systems it will cause some sort of trap -@c or bus error. Cfront considers it an error. -@c * does [appear to] support nested classes within templates. -@c * conversion functions among baseclasses are all usable by -@c a class that's derived from all of those bases. -@c * sizeof works even when the class is defined within its ()'s -@c * conditional expressions work with member fns and pointers to -@c members. -@c * can handle non-trivial declarations of variables within switch -@c statements. -@c -@c Cfront: |
