On Thu, 20 Jan 2022, Jakub Jelinek wrote:
> Hi!
>
> riscv*-*-* are the only modern targets that !HAVE_AS_LEB128 (apparently
> due to some aggressive linker optimizations).
> As the following testcase shows, we mishandle in index_rnglists the
> !HAVE_AS_LEB128 && !have_multiple_function_sections case.
>
> output_rnglists does roughly:
> FOR_EACH_VEC_SAFE_ELT (ranges_table, i, r)
> {
> ...
> if (block_num > 0)
> {
> ...
> if (HAVE_AS_LEB128)
> {
> if (!have_multiple_function_sections)
> {
> // code not using r->*_entry
> continue;
> }
> // code that sometimes doesn't use r->*_entry,
> // sometimes r->begin_entry
> }
> else if (dwarf_split_debug_info)
> {
> // code that uses both r->begin_entry and r->end_entry
> }
> else
> {
> // code not using r->*_entry
> }
> }
> else if (block_num < 0)
> {
> if (!have_multiple_function_sections)
> gcc_unreachable ();
> ...
> }
> }
> and index_rnglists is what sets up those r->{begin,end}_entry members.
> The code did an early if (!have_multiple_function_sections) continue;
> which is fine for the HAVE_AS_LEB128 case, because r->*_entry is not
> used in that case, but not for !HAVE_AS_LEB128 that uses it anyway.
>
> Fixed thusly, tested on the testcase with x86_64 -> riscv64 cross,
> bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
OK.
Thanks,
Richard.
> 2022-01-20 Jakub Jelinek <[email protected]>
>
> PR debug/103874
> * dwarf2out.cc (index_rnglists): For !HAVE_AS_LEB128 and
> block_num > 0, index entry even if !have_multiple_function_sections.
>
> * gcc.dg/debug/dwarf2/pr103874.c: New test.
>
> --- gcc/dwarf2out.cc.jj 2022-01-18 11:58:59.000000000 +0100
> +++ gcc/dwarf2out.cc 2022-01-19 13:30:08.936008194 +0100
> @@ -12094,9 +12094,10 @@ index_rnglists (void)
> if (r->label && r->idx != DW_RANGES_IDX_SKELETON)
> r->idx = rnglist_idx++;
>
> - if (!have_multiple_function_sections)
> - continue;
> int block_num = r->num;
> + if ((HAVE_AS_LEB128 || block_num < 0)
> + && !have_multiple_function_sections)
> + continue;
> if (HAVE_AS_LEB128 && (r->label || r->maybe_new_sec))
> base = false;
> if (block_num > 0)
> --- gcc/testsuite/gcc.dg/debug/dwarf2/pr103874.c.jj 2022-01-19
> 13:35:25.485631843 +0100
> +++ gcc/testsuite/gcc.dg/debug/dwarf2/pr103874.c 2022-01-19
> 13:36:53.608413534 +0100
> @@ -0,0 +1,12 @@
> +/* PR debug/103874 */
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -g -gsplit-dwarf -dA
> -Wno-implicit-function-declaration" } */
> +
> +void
> +foo (void)
> +{
> + {
> + bar ();
> + baz ();
> + }
> +}
>
> Jakub
>
>
--
Richard Biener <[email protected]>
SUSE Software Solutions Germany GmbH, Maxfeldstrasse 5, 90409 Nuernberg,
Germany; GF: Ivo Totev; HRB 36809 (AG Nuernberg)
