[gcc r15-1360] libbacktrace: it's OK if zstd decompressor sees no backward bits

[Ian Lance Taylor]

https://gcc.gnu.org/g:8348f8c22ff1ac61df45d63739e1028f87d6ef88

commit r15-1360-g8348f8c22ff1ac61df45d63739e1028f87d6ef88
Author: Ian Lance Taylor <iant@golang.org>
Date:   Sun Jun 16 15:39:53 2024 -0700

    libbacktrace: it's OK if zstd decompressor sees no backward bits
    
            * elf.c (elf_fetch_bits_backward) Don't fail if no bits are
            available.

Diff:
---
 libbacktrace/elf.c | 9 +--------
 1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/libbacktrace/elf.c b/libbacktrace/elf.c
index 3cd87020b031..735f87525008 100644
--- a/libbacktrace/elf.c
+++ b/libbacktrace/elf.c
@@ -1182,14 +1182,7 @@ elf_fetch_bits_backward (const unsigned char **ppin,
   val = *pval;
 
   if (unlikely (pin <= pinend))
-    {
-      if (bits == 0)
-	{
-	  elf_uncompress_failed ();
-	  return 0;
-	}
-      return 1;
-    }
+    return 1;
 
   pin -= 4;