Okay, I'll send out a trunk patch for review now, too. Ollie
On Sun, Apr 22, 2012 at 10:29 PM, Jeffrey Yasskin <jyass...@google.com> wrote: > > Let's let the discussion _start_ before assuming it'll be protracted. > ;) I don't think it'll kill us to run the next round of testing in > C++98 mode. If the patch doesn't look close to acceptance in a couple > days, I think it'll make sense to put the then-current version into > the google branches while people are agreeing about what to do in the > long run. > > On Sun, Apr 22, 2012 at 8:14 PM, Ollie Wild <a...@google.com> wrote: > > I'd like to get this into the google branches first because this is > > blocking > > testing. > > > > I fully expect this to result in some protracted discussion before it > > can be > > accepted into trunk. > > > > Ollie > > > > > > On Sun, Apr 22, 2012 at 10:10 PM, Jeffrey Yasskin <jyass...@google.com> > > wrote: > >> > >> Could you try to get this into mainline instead of just the google > >> branches? In http://gcc.gnu.org/PR52538, Jonathan sounded like he'd > >> consider accepting it. > >> > >> On Sun, Apr 22, 2012 at 7:54 PM, Ollie Wild <a...@google.com> wrote: > >> > Add new option, -Wreserved-user-defined-literal. > >> > > >> > This option, which is enabled by default, causes the preprocessor to > >> > warn > >> > when a string or character literal is followed by a ud-suffix which > >> > does > >> > not begin with an underscore. According to [lex.ext]p10, this is > >> > ill-formed. > >> > > >> > Also modifies the preprocessor to treat such ill-formed suffixes as > >> > separate > >> > preprocessing tokens. This is consistent with the Clang front end > >> > (see > >> > http://llvm.org/viewvc/llvm-project?view=rev&revision=152287), and > >> > enables > >> > backwards compatibility with code that uses formatting macros from > >> > <inttypes.h>, as in the following code block: > >> > > >> > int main() { > >> > int64_t i64 = 123; > >> > printf("My int64: %"PRId64"\n", i64); > >> > } > >> > > >> > Google ref b/6377711. > >> > > >> > 2012-04-22 Ollie Wild <a...@google.com> > >> > > >> > * gcc/c-family/c-common.c: > >> > * gcc/c-family/c-opts.c (c_common_handle_option): > >> > * gcc/c-family/c.opt: > >> > * gcc/doc/invoke.texi (struct A): > >> > * gcc/testsuite/g++.dg/cpp0x/Wreserved-user-defined-literal.C > >> > (test): > >> > (main): > >> > * libcpp/include/cpplib.h (struct cpp_options): > >> > * libcpp/init.c (cpp_create_reader): > >> > * libcpp/lex.c (lex_raw_string): > >> > (lex_string): > >> > > >> > diff --git a/gcc/c-family/c-common.c b/gcc/c-family/c-common.c > >> > index 1d19251..915dc25 100644 > >> > --- a/gcc/c-family/c-common.c > >> > +++ b/gcc/c-family/c-common.c > >> > @@ -8724,6 +8724,7 @@ static const struct reason_option_codes_t > >> > option_codes[] = { > >> > {CPP_W_NORMALIZE, OPT_Wnormalized_}, > >> > {CPP_W_INVALID_PCH, OPT_Winvalid_pch}, > >> > {CPP_W_WARNING_DIRECTIVE, OPT_Wcpp}, > >> > + {CPP_W_RESERVED_USER_LITERALS, > >> > OPT_Wreserved_user_defined_literal}, > >> > {CPP_W_NONE, 0} > >> > }; > >> > > >> > diff --git a/gcc/c-family/c-opts.c b/gcc/c-family/c-opts.c > >> > index 5118928..dab6ce5 100644 > >> > --- a/gcc/c-family/c-opts.c > >> > +++ b/gcc/c-family/c-opts.c > >> > @@ -509,6 +509,10 @@ c_common_handle_option (size_t scode, const char > >> > *arg, int value, > >> > break; > >> > } > >> > > >> > + case OPT_Wreserved_user_defined_literal: > >> > + cpp_opts->warn_reserved_user_literals = value; > >> > + break; > >> > + > >> > case OPT_Wreturn_type: > >> > warn_return_type = value; > >> > break; > >> > diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt > >> > index 40ff96c..f610513 100644 > >> > --- a/gcc/c-family/c.opt > >> > +++ b/gcc/c-family/c.opt > >> > @@ -589,6 +589,10 @@ Wreorder > >> > C++ ObjC++ Var(warn_reorder) Warning > >> > Warn when the compiler reorders code > >> > > >> > +Wreserved-user-defined-literal > >> > +C++ ObjC++ Warning > >> > +Warn when a string or character literal is followed by a ud-suffix > >> > which does not begin with an underscore. > >> > + > >> > Wreturn-type > >> > C ObjC C++ ObjC++ Var(warn_return_type) Warning > >> > Warn whenever a function's return type defaults to \"int\" (C), or > >> > about inconsistent return types (C++) > >> > diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi > >> > index 1b61e76..d425079 100644 > >> > --- a/gcc/doc/invoke.texi > >> > +++ b/gcc/doc/invoke.texi > >> > @@ -198,7 +198,7 @@ in the following sections. > >> > -fvisibility-ms-compat @gol > >> > -Wabi -Wconversion-null -Wctor-dtor-privacy @gol > >> > -Wdelete-non-virtual-dtor -Wnarrowing -Wnoexcept @gol > >> > --Wnon-virtual-dtor -Wreorder @gol > >> > +-Wnon-virtual-dtor -Wreorder -Wreserved-user-defined-literal @gol > >> > -Weffc++ -Wstrict-null-sentinel @gol > >> > -Wno-non-template-friend -Wold-style-cast @gol > >> > -Woverloaded-virtual -Wno-pmf-conversions @gol > >> > @@ -2474,6 +2474,30 @@ struct A @{ > >> > The compiler will rearrange the member initializers for @samp{i} > >> > and @samp{j} to match the declaration order of the members, emitting > >> > a warning to that effect. This warning is enabled by > >> > @option{-Wall}. > >> > + > >> > +@item -Wreserved-user-defined-literal @r{(C++ and Objective-C++ > >> > only)} > >> > +@opindex Wreserved-user-defined-literal > >> > +@opindex Wno-reserved-user-defined-literal > >> > +Warn when a string or character literal is followed by a ud-suffix > >> > which does > >> > +not begin with an underscore. As a conforming extension, GCC treats > >> > such > >> > +suffixes as separate preprocessing tokens in order to maintain > >> > backwards > >> > +compatibility with code that uses formatting macros from > >> > @code{<inttypes.h>}. > >> > +For example: > >> > + > >> > +@smallexample > >> > +#define __STDC_FORMAT_MACROS > >> > +#include <inttypes.h> > >> > +#include <stdio.h> > >> > + > >> > +int main() @{ > >> > + int64_t i64 = 123; > >> > + printf("My int64: %"PRId64"\n", i64); > >> > +@} > >> > +@end smallexample > >> > + > >> > +In this case, @code{PRId64} is treated as a separate preprocessing > >> > token. > >> > + > >> > +This warning is enabled by default. > >> > @end table > >> > > >> > The following @option{-W@dots{}} options are not affected by > >> > @option{-Wall}. > >> > diff --git > >> > a/gcc/testsuite/g++.dg/cpp0x/Wreserved-user-defined-literal.C > >> > b/gcc/testsuite/g++.dg/cpp0x/Wreserved-user-defined-literal.C > >> > new file mode 100644 > >> > index 0000000..66de5c0 > >> > --- /dev/null > >> > +++ b/gcc/testsuite/g++.dg/cpp0x/Wreserved-user-defined-literal.C > >> > @@ -0,0 +1,29 @@ > >> > +// { dg-do run } > >> > +// { dg-options "-std=c++0x" } > >> > + > >> > +// Make sure -Wreserved-user-defined-literal is enabled by default > >> > and > >> > +// triggers as expected. > >> > + > >> > +#define BAR "bar" > >> > +#define PLUS_ONE + 1 > >> > + > >> > +#include <cstdint> > >> > +#include <cassert> > >> > + > >> > + > >> > +void > >> > +test() > >> > +{ > >> > + char c = '3'PLUS_ONE; // { dg-warning "invalid suffix on > >> > literal" } > >> > + char s[] = "foo"BAR; // { dg-warning "invalid suffix on literal" > >> > } > >> > + > >> > + assert(c == '4'); > >> > + assert(s[3] != '\0'); > >> > + assert(s[3] == 'b'); > >> > +} > >> > + > >> > +int > >> > +main() > >> > +{ > >> > + test(); > >> > +} > >> > diff --git a/libcpp/include/cpplib.h b/libcpp/include/cpplib.h > >> > index bf59d01..84cacb0 100644 > >> > --- a/libcpp/include/cpplib.h > >> > +++ b/libcpp/include/cpplib.h > >> > @@ -427,6 +427,10 @@ struct cpp_options > >> > /* Nonzero for C++ 2011 Standard user-defnied literals. */ > >> > unsigned char user_literals; > >> > > >> > + /* Nonzero means warn when a string or character literal is > >> > followed > >> > by a > >> > + ud-suffix which does not beging with an underscore. */ > >> > + unsigned char warn_reserved_user_literals; > >> > + > >> > /* Holds the name of the target (execution) character set. */ > >> > const char *narrow_charset; > >> > > >> > @@ -906,7 +910,8 @@ enum { > >> > CPP_W_CXX_OPERATOR_NAMES, > >> > CPP_W_NORMALIZE, > >> > CPP_W_INVALID_PCH, > >> > - CPP_W_WARNING_DIRECTIVE > >> > + CPP_W_WARNING_DIRECTIVE, > >> > + CPP_W_RESERVED_USER_LITERALS > >> > }; > >> > > >> > /* Output a diagnostic of some kind. */ > >> > diff --git a/libcpp/init.c b/libcpp/init.c > >> > index 5fa82ca..2688699 100644 > >> > --- a/libcpp/init.c > >> > +++ b/libcpp/init.c > >> > @@ -175,6 +175,7 @@ cpp_create_reader (enum c_lang lang, hash_table > >> > *table, > >> > CPP_OPTION (pfile, warn_variadic_macros) = 1; > >> > CPP_OPTION (pfile, warn_builtin_macro_redefined) = 1; > >> > CPP_OPTION (pfile, warn_normalize) = normalized_C; > >> > + CPP_OPTION (pfile, warn_reserved_user_literals) = 1; > >> > > >> > /* Default CPP arithmetic to something sensible for the host for > >> > the > >> > benefit of dumb users like fix-header. */ > >> > diff --git a/libcpp/lex.c b/libcpp/lex.c > >> > index 0ad9660..ba8ed9e 100644 > >> > --- a/libcpp/lex.c > >> > +++ b/libcpp/lex.c > >> > @@ -1491,14 +1491,30 @@ lex_raw_string (cpp_reader *pfile, cpp_token > >> > *token, const uchar *base, > >> > > >> > if (CPP_OPTION (pfile, user_literals)) > >> > { > >> > + /* According to C++11 [lex.ext]p10, a ud-suffix not starting > >> > with > >> > an > >> > + underscore is ill-formed. Since this breaks programs using > >> > macros > >> > + from inttypes.h, we generate a warning and treat the > >> > ud-suffix > >> > as a > >> > + separate preprocessing token. This approach is under > >> > discussion by > >> > + the standards committee, and has been adopted as a > >> > conforming > >> > + extension by other front ends such as clang. */ > >> > + if (ISALPHA(*cur)) > >> > + { > >> > + // Raise a warning, but do not consume subsequent tokens. > >> > + if (CPP_OPTION (pfile, warn_reserved_user_literals)) > >> > + cpp_warning_with_line (pfile, > >> > CPP_W_RESERVED_USER_LITERALS, > >> > + token->src_loc, 0, > >> > + "invalid suffix on literal; C++11 > >> > requires " > >> > + "a space between literal and > >> > identifier"); > >> > + } > >> > /* Grab user defined literal suffix. */ > >> > - if (ISIDST (*cur)) > >> > + else if (*cur == '_') > >> > { > >> > type = cpp_userdef_string_add_type (type); > >> > ++cur; > >> > + > >> > + while (ISIDNUM (*cur)) > >> > + ++cur; > >> > } > >> > - while (ISIDNUM (*cur)) > >> > - ++cur; > >> > } > >> > > >> > pfile->buffer->cur = cur; > >> > @@ -1606,15 +1622,31 @@ lex_string (cpp_reader *pfile, cpp_token > >> > *token, > >> > const uchar *base) > >> > > >> > if (CPP_OPTION (pfile, user_literals)) > >> > { > >> > + /* According to C++11 [lex.ext]p10, a ud-suffix not starting > >> > with > >> > an > >> > + underscore is ill-formed. Since this breaks programs using > >> > macros > >> > + from inttypes.h, we generate a warning and treat the > >> > ud-suffix > >> > as a > >> > + separate preprocessing token. This approach is under > >> > discussion by > >> > + the standards committee, and has been adopted as a > >> > conforming > >> > + extension by other front ends such as clang. */ > >> > + if (ISALPHA(*cur)) > >> > + { > >> > + // Raise a warning, but do not consume subsequent tokens. > >> > + if (CPP_OPTION (pfile, warn_reserved_user_literals)) > >> > + cpp_warning_with_line (pfile, > >> > CPP_W_RESERVED_USER_LITERALS, > >> > + token->src_loc, 0, > >> > + "invalid suffix on literal; C++11 > >> > requires " > >> > + "a space between literal and > >> > identifier"); > >> > + } > >> > /* Grab user defined literal suffix. */ > >> > - if (ISIDST (*cur)) > >> > + else if (*cur == '_') > >> > { > >> > type = cpp_userdef_char_add_type (type); > >> > type = cpp_userdef_string_add_type (type); > >> > ++cur; > >> > + > >> > + while (ISIDNUM (*cur)) > >> > + ++cur; > >> > } > >> > - while (ISIDNUM (*cur)) > >> > - ++cur; > >> > } > >> > > >> > pfile->buffer->cur = cur; > >> > > >> > -- > >> > This patch is available for review at > >> > http://codereview.appspot.com/6104051 > > > >
