Consider increasing the size of the static symbolization buffer in sanitizer_common

[acmorrow]

Bugzilla Link	52264
Version	unspecified
OS	All
CC	@acmorrow

Extended Description

It appears that there are some 16K static buffers for the symbolizer:

• llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_internal.h

  Line 122 in 12b44bf

  char buffer_[kBufferSize];

• llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_internal.h

  Line 150 in 12b44bf

  static const uptr kBufferSize = 16 * 1024;

I have recently encountered some events where it appears that one or more of these buffers is not sufficient when symbolizing sanitizer failures, leading to messages like:

==4094==WARNING: Symbolizer buffer too small

Would it be possible to expand these to something larger, maybe 1M? While no fixed-sized buffer can handle everything, 16K feels very conservative.

[antonsmyk]

We also have hit this problem with LLVM 10.0.1. After upgrading LLVM to 20.1.7 there is no problem anymore. Although symbolizer code still has some smallish hardcoded buffer sizes, there is no truncation anymore:

$ cat build.log |  sed -n '/ERROR:/,/SUMMARY/p' | grep -E '^\s+#' | while read i; do echo "$i" | wc -c; done | sort -urn | head
64315
47373
47337
42937
42882
30832
22018
21512
21235
21209

I believe acfeb1a fixed this problem in #55460.

I think this case should be closed.