[compiler-rt] Allow libignore to handle modules with multiple executable sections

[fjricci]

Summary

Darwin procmaps added support for section-level memory mappings.
This patch ensures that libignore doesn't Die() when encountering a suppression
file match in a module with multiple executable sections.

[fjricci]

I think the need for this may actually reveal a deeper issue. Only the address range for the first executable section will be added to the suppression. The two ways around that would be to 1) allow the suppression to take multiple ranges or 2) don't use sections in procmaps for executable segments (lsan doesn't care about executable segments anyway)

[fjricci]

Ok, I decided that option 2 seemed like the better call, and took care of it in D35799

lib/sanitizer_common/sanitizer_libignore.cc

for (const auto &mod : modules) {
         if (loaded) {
           Report("%s: called_from_lib suppression '%s' is matched against"
                  " 2 libraries: '%s' and '%s'\n",
                  SanitizerToolName, lib->templ, lib->name, mod.full_name());
           Die();
         }
         loaded = true;
         if (lib->loaded)
-          continue;
+          break;
         VReport(1,
                 "Matched called_from_lib suppression '%s' against library"
                 " '%s'\n",
                 lib->templ, mod.full_name());
         lib->loaded = true;
         lib->name = internal_strdup(mod.full_name());
         const uptr idx =
             atomic_load(&ignored_ranges_count_, memory_order_relaxed);