[clang] [llvm] [UBSan] Implement src:*=sanitize for UBSan (PR #140529)

[Vitaly Buka via cfe-commits]

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@@ -56,10 +56,20 @@ void SanitizerSpecialCaseList::createSanitizerSections() {
 bool SanitizerSpecialCaseList::inSection(SanitizerMask Mask, StringRef Prefix,
                                          StringRef Query,
                                          StringRef Category) const {
-  for (auto &S : SanitizerSections)
-    if ((S.Mask & Mask) &&
-        SpecialCaseList::inSectionBlame(S.Entries, Prefix, Query, Category))
-      return true;
+  return inSectionBlame(Mask, Prefix, Query, Category);
+}
 
-  return false;
+unsigned SanitizerSpecialCaseList::inSectionBlame(SanitizerMask Mask,
+                                                  StringRef Prefix,
+                                                  StringRef Query,
+                                                  StringRef Category) const {
+  for (auto &S : SanitizerSections) {
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vitalybuka wrote:

same src can be matched by multiple sections, and we want the last one

I believe we need to iterate SanitizerSections reverse as well?
Can you please figure out a test case which fails here?

https://github.com/llvm/llvm-project/pull/140529