On Mon, Nov 30, 2020 at 3:12 PM Jakub Jelinek via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> Hi!
>
> I have noticed that while we use DW_LANG_C_plus_plus_14 for -std=c++17
> -gdwarf-5,
> we use DW_LANG_C_plus_plus (aka C++98) for -std=c++20 -gdwarf-5. The
> following patch makes those two match.
>
> Ok for trunk if it passes bootstrap/regtest?
OK.
> 2020-11-30 Jakub Jelinek <ja...@redhat.com>
>
> * dwarf2out.c (gen_compile_unit_die): Treat GNU C++20
> like C++14 for -gdwarf-5.
>
> * g++.dg/debug/dwarf2/lang-cpp17.C: New test.
> * g++.dg/debug/dwarf2/lang-cpp20.C: New test.
>
> --- gcc/dwarf2out.c.jj 2020-11-26 16:22:29.111352844 +0100
> +++ gcc/dwarf2out.c 2020-11-30 15:05:52.601317310 +0100
> @@ -24646,7 +24646,8 @@ gen_compile_unit_die (const char *filena
> language = DW_LANG_C_plus_plus_11;
> else if (strcmp (language_string, "GNU C++14") == 0)
> language = DW_LANG_C_plus_plus_14;
> - else if (strcmp (language_string, "GNU C++17") == 0)
> + else if (strcmp (language_string, "GNU C++17") == 0
> + || strcmp (language_string, "GNU C++20") == 0)
> /* For now. */
> language = DW_LANG_C_plus_plus_14;
> }
> --- gcc/testsuite/g++.dg/debug/dwarf2/lang-cpp17.C.jj 2020-11-30
> 15:06:35.631836747 +0100
> +++ gcc/testsuite/g++.dg/debug/dwarf2/lang-cpp17.C 2020-11-30
> 15:07:19.160350623 +0100
> @@ -0,0 +1,7 @@
> +// { dg-do compile }
> +// { dg-options "-O -std=c++17 -gdwarf-5 -dA" }
> +// For -gdwarf-6 hopefully DW_LANG_C_plus_plus_17
> +// DW_LANG_C_plus_plus_14 = 0x0021
> +// { dg-final { scan-assembler "0x21\[^\n\r]* DW_AT_language" } } */
> +
> +int version;
> --- gcc/testsuite/g++.dg/debug/dwarf2/lang-cpp20.C.jj 2020-11-30
> 15:07:27.436258201 +0100
> +++ gcc/testsuite/g++.dg/debug/dwarf2/lang-cpp20.C 2020-11-30
> 15:07:37.801142442 +0100
> @@ -0,0 +1,7 @@
> +// { dg-do compile }
> +// { dg-options "-O -std=c++20 -gdwarf-5 -dA" }
> +// For -gdwarf-6 hopefully DW_LANG_C_plus_plus_20
> +// DW_LANG_C_plus_plus_14 = 0x0021
> +// { dg-final { scan-assembler "0x21\[^\n\r]* DW_AT_language" } } */
> +
> +int version;
>
> Jakub
>
