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? > > > 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