[PATCH] testsuite: fix dwarf2/utf-1.C with DWARF4

[PATCH] testsuite: fix dwarf2/utf-1.C with DWARF4

[Marek Polacek]

Running
$ make check-c++ RUNTESTFLAGS='--target_board=unix\{-gdwarf-5,-gdwarf-4\} dwarf2.exp=utf-1.C'
shows
FAIL: g++.dg/debug/dwarf2/utf-1.C  -std=gnu++20  scan-assembler-times DW_AT_encoding \\(0x10\\) 3
because with -gdwarf-4 the output is:

  .byte   0x10    # DW_AT_encoding

but with -gdwarf-5 the output is the expected:

                # DW_AT_encoding (0x10)

The difference is caused by the DWARF5 optimize_implicit_const
optimization:
<https://gcc.gnu.org/pipermail/gcc-patches/2016-October/459762.html>

I suppose we could do what testsuite/rust/debug/chartype.rs does
and just run the test with -gdwarf-4.

Tested on x86_64-pc-linux-gnu, ok for trunk?

gcc/testsuite/ChangeLog:

	* g++.dg/debug/dwarf2/utf-1.C: Use -gdwarf-4.  Adjust expected
	output.
---
 gcc/testsuite/g++.dg/debug/dwarf2/utf-1.C | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/gcc/testsuite/g++.dg/debug/dwarf2/utf-1.C b/gcc/testsuite/g++.dg/debug/dwarf2/utf-1.C
index 43b354f1bb5..0ce4d8727d6 100644
--- a/gcc/testsuite/g++.dg/debug/dwarf2/utf-1.C
+++ b/gcc/testsuite/g++.dg/debug/dwarf2/utf-1.C
@@ -1,8 +1,13 @@
 // { dg-do compile { target c++20 } }
-// { dg-options { -gdwarf -dA } }
+// { dg-options { -gdwarf-4 -dA } }
 
 // Test that all three use DW_ATE_UTF.
-// { dg-final { scan-assembler-times {DW_AT_encoding \(0x10\)} 3 } }
+// This test uses -gdwarf-4 since in DWARF5 optimize_implicit_const
+// would optimize the output from:
+//   .byte   0x10    # DW_AT_encoding
+// into:
+//                   # DW_AT_encoding (0x10)
+// { dg-final { scan-assembler-times "0x10\[ \t]\[^\n\r]* DW_AT_encoding" 3 } }
 
 char8_t c8;
 char16_t c16;

base-commit: be240fc6acc9714e66afbfbe6dc193844bfcba05
-- 
2.41.0

Re: [PATCH] testsuite: fix dwarf2/utf-1.C with DWARF4

[Jason Merrill]

On 7/5/23 17:51, Marek Polacek wrote:
> Running
> $ make check-c++ RUNTESTFLAGS='--target_board=unix\{-gdwarf-5,-gdwarf-4\} dwarf2.exp=utf-1.C'
> shows
> FAIL: g++.dg/debug/dwarf2/utf-1.C  -std=gnu++20  scan-assembler-times DW_AT_encoding \\(0x10\\) 3
> because with -gdwarf-4 the output is:
> 
>    .byte   0x10    # DW_AT_encoding
> 
> but with -gdwarf-5 the output is the expected:
> 
>                  # DW_AT_encoding (0x10)
> 
> The difference is caused by the DWARF5 optimize_implicit_const
> optimization:
> <https://gcc.gnu.org/pipermail/gcc-patches/2016-October/459762.html>
> 
> I suppose we could do what testsuite/rust/debug/chartype.rs does
> and just run the test with -gdwarf-4.
> 
> Tested on x86_64-pc-linux-gnu, ok for trunk?

OK.

> gcc/testsuite/ChangeLog:
> 
> 	* g++.dg/debug/dwarf2/utf-1.C: Use -gdwarf-4.  Adjust expected
> 	output.
> ---
>   gcc/testsuite/g++.dg/debug/dwarf2/utf-1.C | 9 +++++++--
>   1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/gcc/testsuite/g++.dg/debug/dwarf2/utf-1.C b/gcc/testsuite/g++.dg/debug/dwarf2/utf-1.C
> index 43b354f1bb5..0ce4d8727d6 100644
> --- a/gcc/testsuite/g++.dg/debug/dwarf2/utf-1.C
> +++ b/gcc/testsuite/g++.dg/debug/dwarf2/utf-1.C
> @@ -1,8 +1,13 @@
>   // { dg-do compile { target c++20 } }
> -// { dg-options { -gdwarf -dA } }
> +// { dg-options { -gdwarf-4 -dA } }
>   
>   // Test that all three use DW_ATE_UTF.
> -// { dg-final { scan-assembler-times {DW_AT_encoding \(0x10\)} 3 } }
> +// This test uses -gdwarf-4 since in DWARF5 optimize_implicit_const
> +// would optimize the output from:
> +//   .byte   0x10    # DW_AT_encoding
> +// into:
> +//                   # DW_AT_encoding (0x10)
> +// { dg-final { scan-assembler-times "0x10\[ \t]\[^\n\r]* DW_AT_encoding" 3 } }
>   
>   char8_t c8;
>   char16_t c16;
> 
> base-commit: be240fc6acc9714e66afbfbe6dc193844bfcba05