On Wed, Nov 12, 2014 at 3:54 PM, Jakub Jelinek <ja...@redhat.com> wrote: > On Wed, Nov 12, 2014 at 03:50:19PM +0100, Mark Wielaard wrote: >> On Mon, 2014-10-13 at 10:33 +0200, Mark Wielaard wrote: >> > On Wed, 2014-10-08 at 12:13 +0200, Mark Wielaard wrote: >> > > This patch was written a long time ago by Jakub and has been in Fedora >> > > gcc for some time. All I did was rebase it to current gcc trunk >> > > and add a testcase. Back when it was originally proposed the issue was >> > > that because DWARF was generated late adding new lang hooks for this >> > > was problematic for LTO. Now that there is a move towards generating >> > > DWARF early I am hoping this patch can finally make it to mainline gcc. >> > >> > Ping. >> >> Ping again. > > I think we want this (also extended for C11/C++11/C++14 afterwards), even > when the early debug bits won't be ready for GCC 5; LTO will just continue > claiming to be old C (or whatever it claims right now), but there is > hope it will be improved for GCC 6. > > But, I can't approve my own patch... Richard, can you live with this?
Why doesn't the patch simply make the FE return sth different in lang_hooks.name? Like "GNU C99" or "GNU ObjC"? Or even better change that to an unsigned int containing DW_LANG_* directly and not a string? I don't see why we would want another langhook whose value is not reflected in TRANSLATION_UNIT_LANGUAGE. Richard. >> > > This lang hook will be more useful when DWARFv5 gets out, which is >> > > supposed to define language identifiers for newer C and C++ versions. >> > > >> > > Previous discussions: >> > > http://gcc.gnu.org/ml/gcc-patches/2009-03/msg00858.html >> > > http://gcc.gnu.org/ml/gcc-patches/2010-04/msg00991.html >> > > >> > > gcc/ChangeLog >> > > >> > > 2009-03-18 Jakub Jelinek <ja...@redhat.com> >> > > >> > > PR debug/38757 >> > > * langhooks.h (struct lang_hooks): Add source_language langhook. >> > > * langhooks-def.h (LANG_HOOKS_SOURCE_LANGUAGE): Define to NULL. >> > > (LANG_HOOKS_INITIALIZER): Add LANG_HOOKS_SOURCE_LANGUAGE. >> > > * dwarf2out.c (add_prototyped_attribute): Add DW_AT_prototype >> > > also for DW_LANG_{C,C99,ObjC}. >> > > (gen_compile_unit_die): Use lang_hooks.source_language () to >> > > determine if DW_LANG_C99 or DW_LANG_C89 should be returned. >> > > >> > > gcc/c/ChangeLog >> > > >> > > 2009-03-18 Jakub Jelinek <ja...@redhat.com> >> > > >> > > PR debug/38757 >> > > * c-lang.c (c_source_language): New function. >> > > (LANG_HOOKS_SOURCE_LANGUAGE): Define. >> > > >> > > gcc/testsuite/ChangeLog >> > > >> > > 2014-10-08 Mark Wielaard <m...@redhat.com> >> > > >> > > PR debug/38757 >> > > * gcc.dg/debug/dwarf2/lang-c89.c: New test. >> > > * gcc.dg/debug/dwarf2/lang-c99.c: Likewise. >> > > --- >> > > gcc/ChangeLog | 11 +++++++++++ >> > > gcc/c/ChangeLog | 6 ++++++ >> > > gcc/c/c-lang.c | 8 ++++++++ >> > > gcc/dwarf2out.c | 19 ++++++++++++++++--- >> > > gcc/langhooks-def.h | 4 +++- >> > > gcc/langhooks.h | 4 ++++ >> > > gcc/testsuite/ChangeLog | 6 ++++++ >> > > gcc/testsuite/gcc.dg/debug/dwarf2/lang-c89.c | 6 ++++++ >> > > gcc/testsuite/gcc.dg/debug/dwarf2/lang-c99.c | 6 ++++++ >> > > 9 files changed, 66 insertions(+), 4 deletions(-) >> > > create mode 100644 gcc/testsuite/gcc.dg/debug/dwarf2/lang-c89.c >> > > create mode 100644 gcc/testsuite/gcc.dg/debug/dwarf2/lang-c99.c >> > > >> > > diff --git a/gcc/c/c-lang.c b/gcc/c/c-lang.c >> > > index 97c0443..dadeb1a 100644 >> > > --- a/gcc/c/c-lang.c >> > > +++ b/gcc/c/c-lang.c >> > > @@ -35,6 +35,12 @@ along with GCC; see the file COPYING3. If not see >> > > >> > > enum c_language_kind c_language = clk_c; >> > > >> > > +static int >> > > +c_source_language (void) >> > > +{ >> > > + return flag_isoc99 ? 1999 : 1989; >> > > +} >> > > + >> > > /* Lang hooks common to C and ObjC are declared in c-objc-common.h; >> > > consequently, there should be very few hooks below. */ >> > > >> > > @@ -44,6 +50,8 @@ enum c_language_kind c_language = clk_c; >> > > #define LANG_HOOKS_INIT c_objc_common_init >> > > #undef LANG_HOOKS_INIT_TS >> > > #define LANG_HOOKS_INIT_TS c_common_init_ts >> > > +#undef LANG_HOOKS_SOURCE_LANGUAGE >> > > +#define LANG_HOOKS_SOURCE_LANGUAGE c_source_language >> > > >> > > /* Each front end provides its own lang hook initializer. */ >> > > struct lang_hooks lang_hooks = LANG_HOOKS_INITIALIZER; >> > > diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c >> > > index 59c05ed..4932cd0 100644 >> > > --- a/gcc/dwarf2out.c >> > > +++ b/gcc/dwarf2out.c >> > > @@ -16708,9 +16708,18 @@ add_bit_size_attribute (dw_die_ref die, tree >> > > decl) >> > > static inline void >> > > add_prototyped_attribute (dw_die_ref die, tree func_type) >> > > { >> > > - if (get_AT_unsigned (comp_unit_die (), DW_AT_language) == DW_LANG_C89 >> > > - && prototype_p (func_type)) >> > > - add_AT_flag (die, DW_AT_prototyped, 1); >> > > + switch (get_AT_unsigned (comp_unit_die (), DW_AT_language)) >> > > + { >> > > + case DW_LANG_C: >> > > + case DW_LANG_C89: >> > > + case DW_LANG_C99: >> > > + case DW_LANG_ObjC: >> > > + if (prototype_p (func_type)) >> > > + add_AT_flag (die, DW_AT_prototyped, 1); >> > > + break; >> > > + default: >> > > + break; >> > > + } >> > > } >> > > >> > > /* Add an 'abstract_origin' attribute below a given DIE. The DIE is >> > > found >> > > @@ -19544,6 +19553,10 @@ gen_compile_unit_die (const char *filename) >> > > language = DW_LANG_ObjC; >> > > else if (strcmp (language_string, "GNU Objective-C++") == 0) >> > > language = DW_LANG_ObjC_plus_plus; >> > > + else if (strcmp (language_string, "GNU C") == 0 >> > > + && lang_hooks.source_language >> > > + && lang_hooks.source_language () >= 1999) >> > > + language = DW_LANG_C99; >> > > else if (dwarf_version >= 5 || !dwarf_strict) >> > > { >> > > if (strcmp (language_string, "GNU Go") == 0) >> > > diff --git a/gcc/langhooks-def.h b/gcc/langhooks-def.h >> > > index e5ae3e3..b6c8dd4 100644 >> > > --- a/gcc/langhooks-def.h >> > > +++ b/gcc/langhooks-def.h >> > > @@ -120,6 +120,7 @@ extern bool lhd_omp_mappable_type (tree); >> > > #define LANG_HOOKS_BLOCK_MAY_FALLTHRU hook_bool_const_tree_true >> > > #define LANG_HOOKS_EH_USE_CXA_END_CLEANUP false >> > > #define LANG_HOOKS_DEEP_UNSHARING false >> > > +#define LANG_HOOKS_SOURCE_LANGUAGE NULL >> > > >> > > /* Attribute hooks. */ >> > > #define LANG_HOOKS_ATTRIBUTE_TABLE NULL >> > > @@ -313,7 +314,8 @@ extern void lhd_end_section (void); >> > > LANG_HOOKS_EH_PROTECT_CLEANUP_ACTIONS, \ >> > > LANG_HOOKS_BLOCK_MAY_FALLTHRU, \ >> > > LANG_HOOKS_EH_USE_CXA_END_CLEANUP, \ >> > > - LANG_HOOKS_DEEP_UNSHARING \ >> > > + LANG_HOOKS_DEEP_UNSHARING, \ >> > > + LANG_HOOKS_SOURCE_LANGUAGE \ >> > > } >> > > >> > > #endif /* GCC_LANG_HOOKS_DEF_H */ >> > > diff --git a/gcc/langhooks.h b/gcc/langhooks.h >> > > index 32e76f9..0022516 100644 >> > > --- a/gcc/langhooks.h >> > > +++ b/gcc/langhooks.h >> > > @@ -485,6 +485,10 @@ struct lang_hooks >> > > gimplification. */ >> > > bool deep_unsharing; >> > > >> > > + /* Return year of the source language standard version if the FE >> > > supports >> > > + multiple versions of the standard. */ >> > > + int (*source_language) (void); >> > > + >> > > /* Whenever you add entries here, make sure you adjust langhooks-def.h >> > > and langhooks.c accordingly. */ >> > > }; >> > > diff --git a/gcc/testsuite/gcc.dg/debug/dwarf2/lang-c89.c >> > > b/gcc/testsuite/gcc.dg/debug/dwarf2/lang-c89.c >> > > new file mode 100644 >> > > index 0000000..6292cf8 >> > > --- /dev/null >> > > +++ b/gcc/testsuite/gcc.dg/debug/dwarf2/lang-c89.c >> > > @@ -0,0 +1,6 @@ >> > > +/* { dg-do compile } */ >> > > +/* { dg-options "-O -std=c89 -g -dA" } */ >> > > +/* DW_LANG_C89 = 0x0001 */ >> > > +/* { dg-final { scan-assembler "0x1.*DW_AT_language" } } */ >> > > + >> > > +int version; >> > > diff --git a/gcc/testsuite/gcc.dg/debug/dwarf2/lang-c99.c >> > > b/gcc/testsuite/gcc.dg/debug/dwarf2/lang-c99.c >> > > new file mode 100644 >> > > index 0000000..1d789fe >> > > --- /dev/null >> > > +++ b/gcc/testsuite/gcc.dg/debug/dwarf2/lang-c99.c >> > > @@ -0,0 +1,6 @@ >> > > +// { dg-do compile } >> > > +// { dg-options "-O -std=c99 -g -dA" } >> > > +// DW_LANG_C99 = 0x000c >> > > +// { dg-final { scan-assembler "0xc.*DW_AT_language" } } */ >> > > + >> > > +int version; >> > > > Jakub
