[PATCH] [RFC] Introduce support for multiple sanitizer blacklists (Clang side).

[Peter Collingbourne]

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Comment at: lib/CodeGen/BackendUtil.cpp:592
@@ -589,1 +591,3 @@
 
+std::unique_ptr<SpecialCaseList> clang::CreateSpecialCaseList(const CodeGenOptions &CGOpts) {
+  auto SCL = llvm::make_unique<SpecialCaseList>();
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Alexey Samsonov wrote:
> Peter Collingbourne wrote:
> > Alexey Samsonov wrote:
> > > See my comment in LLVM part - this file doesn't look like the right place for this function.
> > I was imagining that we could add things like support for ad hoc entries here if we needed it.
> Can you provide an example for "ad hoc" entries which can't be explained by special case list format? It's somewhat unfortunate that you need to modify special case list twice - in Clang CodeGen and before passing it to the backend.
I was referring to the case where you might have an entry on the command line or dynamically loaded from an object file; see my comments in D4546.

I think we can avoid the double construction issue by modifying `SanitizerBlacklist` to only create a `SpecialCaseList` if the user has enabled a sanitizer that uses it.

http://reviews.llvm.org/D4547