https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98776
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Last reconfirmed| |2021-06-30
Ever confirmed|0 |1
Known to work| |11.1.0
CC| |rguenth at gcc dot gnu.org
Known to fail| |10.3.0
Target|x86,arm64 |x86_64-*-* aarch64
Status|UNCONFIRMED |NEW
--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
Confirmed.
void __attribute__((noipa)) foo() { }
int main() { foo (); }
> gcc-10 t.c -g -fpatchable-function-entry=16 -O
> gdb ./a.out
GNU gdb (GDB; SUSE Linux Enterprise 15) 10.1
...
(gdb) disassemble foo
Dump of assembler code for function foo:
0x00000000004004a6 <+0>: ret
End of assembler dump.
(gdb) b foo
Breakpoint 1 at 0x400496 (2 locations)
so the symbol is at 0x400496 but low-pc is 0x4004a6
On trunk the FDE start/end labels look correct:
foo:
.LFB0:
.cfi_startproc
.section __patchable_function_entries,"awo",@progbits,foo
.align 8
.quad .LPFE1
.text
.LPFE1:
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
ret
.cfi_endproc
.LFE0:
and it seems to work there. Quick verification shows it works with GCC 11+
but fails with GCC 10 which has
foo:
.section __patchable_function_entries,"aw",@progbits
.align 8
.quad .LPFE1
.text
.LPFE1:
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
.LFB0:
.file 1 "t.c"
.loc 1 1 35 view -0
.cfi_startproc
.loc 1 1 37 view .LVU1
ret
.cfi_endproc
.LFE0:
.size foo, .-foo
