[PATCH] D16440: [ThinLTO] Link in only necessary DICompileUnit operands

[Akira Hatanaka via llvm-commits]

ahatanak added a subscriber: ahatanak.

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Comment at: lib/Linker/IRMover.cpp:1374
@@ +1373,3 @@
+                    &GValMaterializer);
+    std::vector<DICompositeType *> RetainWorklist;
+    if (!IsMetadataLinkingPostpass) {
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While I was building a project using thin-LTO, I found out that the call to MapMetadata here causes an assert if CU-getSubprograms().get() returns null (the assert is triggered in MapMetadataImpl when isa<MDString> is called on a null ptr). Should we check whether CU->getSubprograms() is empty before calling the function? Mehdi also suggested that we can do the check inside MapMetadaImpl and have it return null if the first argument is null. That might be better if there are other call sites that passes a null pointer as the first argument.


http://reviews.llvm.org/D16440