| Message ID | 20180222145615.GV5867@tucnak |
|---|---|
| State | New |
| Headers | show |
| Series | Correct debug for -mcall-ms2sysv-xlogues stubs (PR target/83917, take 2) | expand |
On Thu, Feb 22, 2018 at 03:56:15PM +0100, Jakub Jelinek wrote: > Ok for trunk if it passes bootstrap/regtest on x86_64-linux and i686-linux? Now successfully bootstrapped/regtested on these targets. > 2018-02-22 Jakub Jelinek <jakub@redhat.com> > > PR debug/83917 > * config/i386/i386-asm.h (PACKAGE_VERSION, PACKAGE_NAME, > PACKAGE_STRING, PACKAGE_TARNAME, PACKAGE_URL): Undefine between > inclusion of auto-target.h and auto-host.h. > (USE_GAS_CFI_DIRECTIVES): Define if not defined already based on > __GCC_HAVE_DWARF2_CFI_ASM. > (cfi_startproc, cfi_endproc, cfi_adjust_cfa_offset, > cfi_def_cfa_register, cfi_def_cfa, cfi_register, cfi_offset, cfi_push, > cfi_pop): Define. > * config/i386/cygwin.S: Don't include auto-host.h here, just > define USE_GAS_CFI_DIRECTIVES to 1 or 0 and include i386-asm.h. > (cfi_startproc, cfi_endproc, cfi_adjust_cfa_offset, > cfi_def_cfa_register, cfi_register, cfi_push, cfi_pop): Remove. > * config/i386/resms64fx.h: Add cfi_* directives. > * config/i386/resms64x.h: Likewise. Jakub
Sorry for the dropping the ball on this and thank you Jakub for stepping in! I've had a patch set sort-of rotting in my local repo, but I like yours better. I think I had gotten hung up on trying to figure out how to write a test for this, and like you I just tested mine manually in gdb. I do have one correction though. On 02/22/2018 08:56 AM, Jakub Jelinek wrote: > Hi! > > On Sat, Jan 20, 2018 at 06:01:16PM -0600, Daniel Santos wrote: >> Thanks. I like the idea of commonizing the macros for consistency. > Didn't see a progress on this P3 for a while, so I've written this > version of the patch; no tests though, what I've been using in testing was: > /* { dg-do compile { target lp64 } } */ > /* { dg-options "-mno-avx -msse2 -mcall-ms2sysv-xlogues -O2" } */ > > void __attribute__((sysv_abi, noipa)) > foo (void) > { > } > > static void __attribute__((sysv_abi)) (*volatile foop) () = foo; > > void __attribute__((ms_abi, noipa)) > bar (void) > { > foop (); > } > > int > main () > { > bar (); > return 0; > } > > with/without -fno-omit-frame-pointer, disas bar; b on the tail > call in there, stepi; bt (which before the patch failed, now works), > also up; p $rbp to see if %rbp has been properly declared to be saved. > There is no need to cfi_startproc/cfi_endproc for every single entrypoint in > there, it is enough if the whole range is covered. On the other side > we need the cfi_offset for the frame pointer case, otherwise up; p/x $rbp > doesn't work properly. > > Ok for trunk if it passes bootstrap/regtest on x86_64-linux and i686-linux? > > 2018-02-22 Jakub Jelinek <jakub@redhat.com> > > PR debug/83917 > * config/i386/i386-asm.h (PACKAGE_VERSION, PACKAGE_NAME, > PACKAGE_STRING, PACKAGE_TARNAME, PACKAGE_URL): Undefine between > inclusion of auto-target.h and auto-host.h. > (USE_GAS_CFI_DIRECTIVES): Define if not defined already based on > __GCC_HAVE_DWARF2_CFI_ASM. > (cfi_startproc, cfi_endproc, cfi_adjust_cfa_offset, > cfi_def_cfa_register, cfi_def_cfa, cfi_register, cfi_offset, cfi_push, > cfi_pop): Define. > * config/i386/cygwin.S: Don't include auto-host.h here, just > define USE_GAS_CFI_DIRECTIVES to 1 or 0 and include i386-asm.h. > (cfi_startproc, cfi_endproc, cfi_adjust_cfa_offset, > cfi_def_cfa_register, cfi_register, cfi_push, cfi_pop): Remove. > * config/i386/resms64fx.h: Add cfi_* directives. > * config/i386/resms64x.h: Likewise. > > --- libgcc/config/i386/i386-asm.h.jj 2018-01-03 10:42:56.317763517 +0100 > +++ libgcc/config/i386/i386-asm.h 2018-02-22 15:33:43.812922298 +0100 > @@ -27,8 +27,47 @@ see the files COPYING3 and COPYING.RUNTI > #define I386_ASM_H > > #include "auto-target.h" > +#undef PACKAGE_VERSION > +#undef PACKAGE_NAME > +#undef PACKAGE_STRING > +#undef PACKAGE_TARNAME > +#undef PACKAGE_URL This is a beautiful, temporary(?) fix to an ugly problem! > #include "auto-host.h" > > +#ifndef USE_GAS_CFI_DIRECTIVES > +# ifdef __GCC_HAVE_DWARF2_CFI_ASM > +# define USE_GAS_CFI_DIRECTIVES 1 > +# else > +# define USE_GAS_CFI_DIRECTIVES 0 > +# endif > +#endif > +#if USE_GAS_CFI_DIRECTIVES > +# define cfi_startproc() .cfi_startproc > +# define cfi_endproc() .cfi_endproc > +# define cfi_adjust_cfa_offset(X) .cfi_adjust_cfa_offset X > +# define cfi_def_cfa_register(X) .cfi_def_cfa_register X > +# define cfi_def_cfa(R,O) .cfi_def_cfa R, O > +# define cfi_register(D,S) .cfi_register D, S > +# define cfi_offset(R,O) .cfi_offset R, O > +# ifdef __x86_64__ > +# define cfi_push(X) .cfi_adjust_cfa_offset 8; .cfi_rel_offset X, 0 > +# define cfi_pop(X) .cfi_adjust_cfa_offset -8; .cfi_restore X > +# else > +# define cfi_push(X) .cfi_adjust_cfa_offset 4; .cfi_rel_offset X, 0 > +# define cfi_pop(X) .cfi_adjust_cfa_offset -4; .cfi_restore X > +# endif > +#else > +# define cfi_startproc() > +# define cfi_endproc() > +# define cfi_adjust_cfa_offset(X) > +# define cfi_def_cfa_register(X) > +# define cfi_def_cfa(R,O) > +# define cfi_register(D,S) > +# define cfi_offset(R,O) > +# define cfi_push(X) > +# define cfi_pop(X) > +#endif > + > #define PASTE2(a, b) PASTE2a(a, b) > #define PASTE2a(a, b) a ## b > > --- libgcc/config/i386/cygwin.S.jj 2018-01-03 10:42:56.309763515 +0100 > +++ libgcc/config/i386/cygwin.S 2018-02-22 15:30:34.597925496 +0100 > @@ -23,31 +23,13 @@ > * <http://www.gnu.org/licenses/>. > */ > > -#include "auto-host.h" The following include should be here. +#include "i386-asm.h" > - > #ifdef HAVE_GAS_CFI_SECTIONS_DIRECTIVE > +# define USE_GAS_CFI_DIRECTIVES 1 > .cfi_sections .debug_frame > -# define cfi_startproc() .cfi_startproc > -# define cfi_endproc() .cfi_endproc > -# define cfi_adjust_cfa_offset(X) .cfi_adjust_cfa_offset X > -# define cfi_def_cfa_register(X) .cfi_def_cfa_register X > -# define cfi_register(D,S) .cfi_register D, S > -# ifdef __x86_64__ > -# define cfi_push(X) .cfi_adjust_cfa_offset 8; .cfi_rel_offset X, 0 > -# define cfi_pop(X) .cfi_adjust_cfa_offset -8; .cfi_restore X > -# else > -# define cfi_push(X) .cfi_adjust_cfa_offset 4; .cfi_rel_offset X, 0 > -# define cfi_pop(X) .cfi_adjust_cfa_offset -4; .cfi_restore X > -# endif > #else > -# define cfi_startproc() > -# define cfi_endproc() > -# define cfi_adjust_cfa_offset(X) > -# define cfi_def_cfa_register(X) > -# define cfi_register(D,S) > -# define cfi_push(X) > -# define cfi_pop(X) > -#endif /* HAVE_GAS_CFI_SECTIONS_DIRECTIVE */ > +# define USE_GAS_CFI_DIRECTIVES 0 > +#endif > +#include "i386-asm.h" ...instead of where it is above. ^^ > > #ifdef L_chkstk > /* Function prologue calls __chkstk to probe the stack when allocating more > --- libgcc/config/i386/resms64fx.h.jj 2018-01-03 10:42:56.246763504 +0100 > +++ libgcc/config/i386/resms64fx.h 2018-02-22 15:14:53.391623798 +0100 > @@ -33,6 +33,9 @@ see the files COPYING3 and COPYING.RUNTI > * from the function. */ > > .text > + cfi_startproc() > + cfi_offset(%rbp, -16) > + cfi_def_cfa(%rbp, 16) > MS2SYSV_STUB_BEGIN(resms64fx_17) > mov -0x68(%rsi),%r15 > MS2SYSV_STUB_BEGIN(resms64fx_16) > @@ -48,7 +51,9 @@ MS2SYSV_STUB_BEGIN(resms64fx_12) > SSE_RESTORE > mov -0x38(%rsi),%rsi > leaveq > + cfi_def_cfa(%rsp, 8) > ret > + cfi_endproc() > MS2SYSV_STUB_END(resms64fx_12) > MS2SYSV_STUB_END(resms64fx_13) > MS2SYSV_STUB_END(resms64fx_14) > --- libgcc/config/i386/resms64x.h.jj 2018-01-03 10:42:56.308763515 +0100 > +++ libgcc/config/i386/resms64x.h 2018-02-22 15:02:00.400106064 +0100 > @@ -32,6 +32,8 @@ see the files COPYING3 and COPYING.RUNTI > * function. */ > > .text > + cfi_startproc() > + cfi_def_cfa(%r10, 8) > MS2SYSV_STUB_BEGIN(resms64x_18) > mov -0x70(%rsi),%r15 > MS2SYSV_STUB_BEGIN(resms64x_17) > @@ -49,7 +51,9 @@ MS2SYSV_STUB_BEGIN(resms64x_12) > SSE_RESTORE > mov -0x38(%rsi),%rsi > mov %r10,%rsp > + cfi_def_cfa_register(%rsp) > ret > + cfi_endproc() > MS2SYSV_STUB_END(resms64x_12) > MS2SYSV_STUB_END(resms64x_13) > MS2SYSV_STUB_END(resms64x_14) > > > Jakub > Thanks Jakub! Daniel
On Sun, Feb 25, 2018 at 05:56:28PM -0600, Daniel Santos wrote: > > --- libgcc/config/i386/i386-asm.h.jj 2018-01-03 10:42:56.317763517 +0100 > > +++ libgcc/config/i386/i386-asm.h 2018-02-22 15:33:43.812922298 +0100 > > @@ -27,8 +27,47 @@ see the files COPYING3 and COPYING.RUNTI > > #define I386_ASM_H > > > > #include "auto-target.h" > > +#undef PACKAGE_VERSION > > +#undef PACKAGE_NAME > > +#undef PACKAGE_STRING > > +#undef PACKAGE_TARNAME > > +#undef PACKAGE_URL > > This is a beautiful, temporary(?) fix to an ugly problem! > > > #include "auto-host.h" > > --- libgcc/config/i386/cygwin.S.jj 2018-01-03 10:42:56.309763515 +0100 > > +++ libgcc/config/i386/cygwin.S 2018-02-22 15:30:34.597925496 +0100 > > @@ -23,31 +23,13 @@ > > * <http://www.gnu.org/licenses/>. > > */ > > > > -#include "auto-host.h" > > The following include should be here. > > +#include "i386-asm.h" I don't understand this. i386-asm.h needs (both before my patch and after it) both auto-host.h and auto-target.h, as it tests HAVE_GAS_SECTIONS_DIRECTIVE (this one newly, comes from cygwin.S) HAVE_GAS_HIDDEN macros defined in auto-host.h and HAVE_AS_AVX macro defined in auto-target.h. Including auto-host.h when i386-asm.h will include it again just doesn't work, these headers don't have multiple inclusion guards. And only including auto-target.h will work only if the .hidden and .cfi_sections .debug_frame tests are duplicated from gcc/configure.ac to libgcc/configure.ac, then we could include just auto-target.h in i386-asm.h. I've just followed what i386-asm.h has been doing. Jakub
On 02/22/2018 07:56 AM, Jakub Jelinek wrote: > Hi! > > On Sat, Jan 20, 2018 at 06:01:16PM -0600, Daniel Santos wrote: >> Thanks. I like the idea of commonizing the macros for consistency. > > Didn't see a progress on this P3 for a while, so I've written this > version of the patch; no tests though, what I've been using in testing was: > /* { dg-do compile { target lp64 } } */ > /* { dg-options "-mno-avx -msse2 -mcall-ms2sysv-xlogues -O2" } */ > > void __attribute__((sysv_abi, noipa)) > foo (void) > { > } > > static void __attribute__((sysv_abi)) (*volatile foop) () = foo; > > void __attribute__((ms_abi, noipa)) > bar (void) > { > foop (); > } > > int > main () > { > bar (); > return 0; > } > > with/without -fno-omit-frame-pointer, disas bar; b on the tail > call in there, stepi; bt (which before the patch failed, now works), > also up; p $rbp to see if %rbp has been properly declared to be saved. > There is no need to cfi_startproc/cfi_endproc for every single entrypoint in > there, it is enough if the whole range is covered. On the other side > we need the cfi_offset for the frame pointer case, otherwise up; p/x $rbp > doesn't work properly. > > Ok for trunk if it passes bootstrap/regtest on x86_64-linux and i686-linux? > > 2018-02-22 Jakub Jelinek <jakub@redhat.com> > > PR debug/83917 > * config/i386/i386-asm.h (PACKAGE_VERSION, PACKAGE_NAME, > PACKAGE_STRING, PACKAGE_TARNAME, PACKAGE_URL): Undefine between > inclusion of auto-target.h and auto-host.h. > (USE_GAS_CFI_DIRECTIVES): Define if not defined already based on > __GCC_HAVE_DWARF2_CFI_ASM. > (cfi_startproc, cfi_endproc, cfi_adjust_cfa_offset, > cfi_def_cfa_register, cfi_def_cfa, cfi_register, cfi_offset, cfi_push, > cfi_pop): Define. > * config/i386/cygwin.S: Don't include auto-host.h here, just > define USE_GAS_CFI_DIRECTIVES to 1 or 0 and include i386-asm.h. > (cfi_startproc, cfi_endproc, cfi_adjust_cfa_offset, > cfi_def_cfa_register, cfi_register, cfi_push, cfi_pop): Remove. > * config/i386/resms64fx.h: Add cfi_* directives. > * config/i386/resms64x.h: Likewise. It's a bit ugly. But OK. We can refine further if needed. jeff
On 02/26/2018 02:20 AM, Jakub Jelinek wrote: > On Sun, Feb 25, 2018 at 05:56:28PM -0600, Daniel Santos wrote: >>> --- libgcc/config/i386/i386-asm.h.jj 2018-01-03 10:42:56.317763517 +0100 >>> +++ libgcc/config/i386/i386-asm.h 2018-02-22 15:33:43.812922298 +0100 >>> @@ -27,8 +27,47 @@ see the files COPYING3 and COPYING.RUNTI >>> #define I386_ASM_H >>> >>> #include "auto-target.h" >>> +#undef PACKAGE_VERSION >>> +#undef PACKAGE_NAME >>> +#undef PACKAGE_STRING >>> +#undef PACKAGE_TARNAME >>> +#undef PACKAGE_URL >> This is a beautiful, temporary(?) fix to an ugly problem! >> >>> #include "auto-host.h" >>> --- libgcc/config/i386/cygwin.S.jj 2018-01-03 10:42:56.309763515 +0100 >>> +++ libgcc/config/i386/cygwin.S 2018-02-22 15:30:34.597925496 +0100 >>> @@ -23,31 +23,13 @@ >>> * <http://www.gnu.org/licenses/>. >>> */ >>> >>> -#include "auto-host.h" >> The following include should be here. >> >> +#include "i386-asm.h" > I don't understand this. i386-asm.h needs (both before my patch and after > it) both auto-host.h and auto-target.h, as it tests > HAVE_GAS_SECTIONS_DIRECTIVE (this one newly, comes from cygwin.S) The problem is that HAVE_GAS_SECTIONS_DIRECTIVE gets defined (or not) in ../../gcc/auto-host.h, but you are testing it before including auto-host.h, either directly or via i386-asm.h. So if i386-asm.h depends upon HAVE_GAS_SECTIONS_DIRECTIVE first being defined then it is a circular dependency. In its current form, cygwin.S would never define USE_GAS_CFI_DIRECTIVES prior to including i386-asm.h and also never emit .cfi_sections .debug_frame and rather or not USE_GAS_CFI_DIRECTIVES ends up being defined to 1 or 0 depends upon the test of __GCC_HAVE_DWARF2_CFI_ASM in i386-asm.h. So this area is new for me, but I don't understand why we're testing HAVE_GAS_SECTIONS_DIRECTIVE in cygwin.S and __GCC_HAVE_DWARF2_CFI_ASM when included from one of the stubs. Is this an error, or a lack of my understanding or both? :) > HAVE_GAS_HIDDEN > macros defined in auto-host.h > and > HAVE_AS_AVX > macro defined in auto-target.h. > Including auto-host.h when i386-asm.h will include it again just doesn't > work, these headers don't have multiple inclusion guards. And only including > auto-target.h will work only if the > .hidden > and > .cfi_sections .debug_frame > tests are duplicated from gcc/configure.ac to libgcc/configure.ac, then we > could include just auto-target.h in i386-asm.h. > I've just followed what i386-asm.h has been doing. And it's possible that I failed to test something correctly before presuming it to be available, although I *think* the test for .hidden is good. > > Jakub > Thanks for your work on this. If we need to test for CFI directives differently when being included from cygwin.S, maybe we can just define a simple cpp macro to indicate this and let i386-asm.h encapsulate the implementation of it (e.g., testing HAVE_GAS_SECTIONS_DIRECTIVE or __GCC_HAVE_DWARF2_CFI_ASM as appropriate). Ultimately, the proper cleanup will be moving these tests out of {gcc,libgcc}/configure.ac and into .m4 files in the root config directory so that we don't uglify them with massive copy & pastes. These tests are also fairly complex as there are a lot of dependencies. m4 isn't my strong suite, but I can look at this after we're out of code freeze. Daniel
--- libgcc/config/i386/i386-asm.h.jj 2018-01-03 10:42:56.317763517 +0100 +++ libgcc/config/i386/i386-asm.h 2018-02-22 15:33:43.812922298 +0100 @@ -27,8 +27,47 @@ see the files COPYING3 and COPYING.RUNTI #define I386_ASM_H #include "auto-target.h" +#undef PACKAGE_VERSION +#undef PACKAGE_NAME +#undef PACKAGE_STRING +#undef PACKAGE_TARNAME +#undef PACKAGE_URL #include "auto-host.h" +#ifndef USE_GAS_CFI_DIRECTIVES +# ifdef __GCC_HAVE_DWARF2_CFI_ASM +# define USE_GAS_CFI_DIRECTIVES 1 +# else +# define USE_GAS_CFI_DIRECTIVES 0 +# endif +#endif +#if USE_GAS_CFI_DIRECTIVES +# define cfi_startproc() .cfi_startproc +# define cfi_endproc() .cfi_endproc +# define cfi_adjust_cfa_offset(X) .cfi_adjust_cfa_offset X +# define cfi_def_cfa_register(X) .cfi_def_cfa_register X +# define cfi_def_cfa(R,O) .cfi_def_cfa R, O +# define cfi_register(D,S) .cfi_register D, S +# define cfi_offset(R,O) .cfi_offset R, O +# ifdef __x86_64__ +# define cfi_push(X) .cfi_adjust_cfa_offset 8; .cfi_rel_offset X, 0 +# define cfi_pop(X) .cfi_adjust_cfa_offset -8; .cfi_restore X +# else +# define cfi_push(X) .cfi_adjust_cfa_offset 4; .cfi_rel_offset X, 0 +# define cfi_pop(X) .cfi_adjust_cfa_offset -4; .cfi_restore X +# endif +#else +# define cfi_startproc() +# define cfi_endproc() +# define cfi_adjust_cfa_offset(X) +# define cfi_def_cfa_register(X) +# define cfi_def_cfa(R,O) +# define cfi_register(D,S) +# define cfi_offset(R,O) +# define cfi_push(X) +# define cfi_pop(X) +#endif + #define PASTE2(a, b) PASTE2a(a, b) #define PASTE2a(a, b) a ## b --- libgcc/config/i386/cygwin.S.jj 2018-01-03 10:42:56.309763515 +0100 +++ libgcc/config/i386/cygwin.S 2018-02-22 15:30:34.597925496 +0100 @@ -23,31 +23,13 @@ * <http://www.gnu.org/licenses/>. */ -#include "auto-host.h" - #ifdef HAVE_GAS_CFI_SECTIONS_DIRECTIVE +# define USE_GAS_CFI_DIRECTIVES 1 .cfi_sections .debug_frame -# define cfi_startproc() .cfi_startproc -# define cfi_endproc() .cfi_endproc -# define cfi_adjust_cfa_offset(X) .cfi_adjust_cfa_offset X -# define cfi_def_cfa_register(X) .cfi_def_cfa_register X -# define cfi_register(D,S) .cfi_register D, S -# ifdef __x86_64__ -# define cfi_push(X) .cfi_adjust_cfa_offset 8; .cfi_rel_offset X, 0 -# define cfi_pop(X) .cfi_adjust_cfa_offset -8; .cfi_restore X -# else -# define cfi_push(X) .cfi_adjust_cfa_offset 4; .cfi_rel_offset X, 0 -# define cfi_pop(X) .cfi_adjust_cfa_offset -4; .cfi_restore X -# endif #else -# define cfi_startproc() -# define cfi_endproc() -# define cfi_adjust_cfa_offset(X) -# define cfi_def_cfa_register(X) -# define cfi_register(D,S) -# define cfi_push(X) -# define cfi_pop(X) -#endif /* HAVE_GAS_CFI_SECTIONS_DIRECTIVE */ +# define USE_GAS_CFI_DIRECTIVES 0 +#endif +#include "i386-asm.h" #ifdef L_chkstk /* Function prologue calls __chkstk to probe the stack when allocating more --- libgcc/config/i386/resms64fx.h.jj 2018-01-03 10:42:56.246763504 +0100 +++ libgcc/config/i386/resms64fx.h 2018-02-22 15:14:53.391623798 +0100 @@ -33,6 +33,9 @@ see the files COPYING3 and COPYING.RUNTI * from the function. */ .text + cfi_startproc() + cfi_offset(%rbp, -16) + cfi_def_cfa(%rbp, 16) MS2SYSV_STUB_BEGIN(resms64fx_17) mov -0x68(%rsi),%r15 MS2SYSV_STUB_BEGIN(resms64fx_16) @@ -48,7 +51,9 @@ MS2SYSV_STUB_BEGIN(resms64fx_12) SSE_RESTORE mov -0x38(%rsi),%rsi leaveq + cfi_def_cfa(%rsp, 8) ret + cfi_endproc() MS2SYSV_STUB_END(resms64fx_12) MS2SYSV_STUB_END(resms64fx_13) MS2SYSV_STUB_END(resms64fx_14) --- libgcc/config/i386/resms64x.h.jj 2018-01-03 10:42:56.308763515 +0100 +++ libgcc/config/i386/resms64x.h 2018-02-22 15:02:00.400106064 +0100 @@ -32,6 +32,8 @@ see the files COPYING3 and COPYING.RUNTI * function. */ .text + cfi_startproc() + cfi_def_cfa(%r10, 8) MS2SYSV_STUB_BEGIN(resms64x_18) mov -0x70(%rsi),%r15 MS2SYSV_STUB_BEGIN(resms64x_17) @@ -49,7 +51,9 @@ MS2SYSV_STUB_BEGIN(resms64x_12) SSE_RESTORE mov -0x38(%rsi),%rsi mov %r10,%rsp + cfi_def_cfa_register(%rsp) ret + cfi_endproc() MS2SYSV_STUB_END(resms64x_12) MS2SYSV_STUB_END(resms64x_13) MS2SYSV_STUB_END(resms64x_14)
Hi! On Sat, Jan 20, 2018 at 06:01:16PM -0600, Daniel Santos wrote: > Thanks. I like the idea of commonizing the macros for consistency. Didn't see a progress on this P3 for a while, so I've written this version of the patch; no tests though, what I've been using in testing was: /* { dg-do compile { target lp64 } } */ /* { dg-options "-mno-avx -msse2 -mcall-ms2sysv-xlogues -O2" } */ void __attribute__((sysv_abi, noipa)) foo (void) { } static void __attribute__((sysv_abi)) (*volatile foop) () = foo; void __attribute__((ms_abi, noipa)) bar (void) { foop (); } int main () { bar (); return 0; } with/without -fno-omit-frame-pointer, disas bar; b on the tail call in there, stepi; bt (which before the patch failed, now works), also up; p $rbp to see if %rbp has been properly declared to be saved. There is no need to cfi_startproc/cfi_endproc for every single entrypoint in there, it is enough if the whole range is covered. On the other side we need the cfi_offset for the frame pointer case, otherwise up; p/x $rbp doesn't work properly. Ok for trunk if it passes bootstrap/regtest on x86_64-linux and i686-linux? 2018-02-22 Jakub Jelinek <jakub@redhat.com> PR debug/83917 * config/i386/i386-asm.h (PACKAGE_VERSION, PACKAGE_NAME, PACKAGE_STRING, PACKAGE_TARNAME, PACKAGE_URL): Undefine between inclusion of auto-target.h and auto-host.h. (USE_GAS_CFI_DIRECTIVES): Define if not defined already based on __GCC_HAVE_DWARF2_CFI_ASM. (cfi_startproc, cfi_endproc, cfi_adjust_cfa_offset, cfi_def_cfa_register, cfi_def_cfa, cfi_register, cfi_offset, cfi_push, cfi_pop): Define. * config/i386/cygwin.S: Don't include auto-host.h here, just define USE_GAS_CFI_DIRECTIVES to 1 or 0 and include i386-asm.h. (cfi_startproc, cfi_endproc, cfi_adjust_cfa_offset, cfi_def_cfa_register, cfi_register, cfi_push, cfi_pop): Remove. * config/i386/resms64fx.h: Add cfi_* directives. * config/i386/resms64x.h: Likewise. Jakub