[compiler-rt] PR#39514 Support versioned llvm-symbolizer binaries

Some linux distributions produce versioned llvm-symbolizer binaries,
e.g. my llvm-11 installation puts the symbolizer binary at
/usr/bin/llvm-symbolizer-11.0.0 . However if you then try to run
a binary containing ASAN with
ASAN_SYMBOLIZER_PATH=..../llvm-symbolizer-FOO , it will fail on startup
with "isn't a known symbolizer".

Although it is possible to work around this by setting up symlinks,
that's kindof ugly - supporting versioned binaries is a nicer solution.
(There are now multiple stack overflow and blog posts talking about
 this exact issue :) .)

Originally added in:
https://reviews.llvm.org/D8285

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D97682

Author: ahunt

compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp

@@ -408,10 +408,12 @@ static SymbolizerTool *ChooseExternalSymbolizer(LowLevelAllocator *allocator) {
   }
 
   const char *binary_name = path ? StripModuleName(path) : "";
+  static const char kLLVMSymbolizerPrefix[] = "llvm-symbolizer";
   if (path && path[0] == '\0') {
     VReport(2, "External symbolizer is explicitly disabled.\n");
     return nullptr;
-  } else if (!internal_strcmp(binary_name, "llvm-symbolizer")) {
+  } else if (!internal_strncmp(binary_name, kLLVMSymbolizerPrefix,
+                               internal_strlen(kLLVMSymbolizerPrefix))) {
     VReport(2, "Using llvm-symbolizer at user-specified path: %s\n", path);
     return new(*allocator) LLVMSymbolizer(path, allocator);
   } else if (!internal_strcmp(binary_name, "atos")) {