[LLVMdev] Format of special case list for sanitizers

[Ryan Govostes]

The documentation for the sanitizer special case list format[0] says,

> The meanining of * in regular expression for entity names is different - it is treated as in shell wildcarding.


In SpecialCaseList::parse, we see that this is just replacing * with .*:

    // Replace * with .*
    for (size_t pos = 0; (pos = Regexp.find("*", pos)) != std::string::npos;
         pos += strlen(".*")) {
      Regexp.replace(pos, strlen("*"), ".*");
    }

This seems to introduce more problems than it solves, since (i) this doesn’t really behave like a shell globbing wildcard as advertised, and (ii) if the user tries to use * as a regex quantifier, this will match incorrectly: A* matches the empty string and any number of As, while A.* matches all strings that start with at least one A.

If it’s forgivable to break compatibility here, we should do regular expressions _or_ shell globbing, and not a hybrid format.

I’d prefer shell globbing for paths in src entities, but that isn’t as useful for function names. Most filenames will contain periods, which also need to be escaped properly as regular expressions. (This also limits the usefulness of treating literals separately.)

(Just a note: the way that regular expressions are concatenated in ::parse appears to have a bug if a pattern contains a pipe.)

Ryan


0: http://clang.llvm.org/docs/SanitizerSpecialCaseList.html


diff --git a/lib/Support/SpecialCaseList.cpp b/lib/Support/SpecialCaseList.cpp
index c312cc1..2972cb1 100644
--- a/lib/Support/SpecialCaseList.cpp
+++ b/lib/Support/SpecialCaseList.cpp
@@ -133,7 +133,7 @@ bool SpecialCaseList::parse(const MemoryBuffer *MB, std::string &Error) {
     // Add this regexp into the proper group by its prefix.
     if (!Regexps[Prefix][Category].empty())
       Regexps[Prefix][Category] += "|";
-    Regexps[Prefix][Category] += "^" + Regexp + "$";
+    Regexps[Prefix][Category] += "^(" + Regexp + ")$)";
   }
   return true;
 }