[PATCH] D37042: Teach clang to tolerate the 'p = nullptr + n' idiom used by glibc

[Andy Kaylor via Phabricator via cfe-commits]

andrew.w.kaylor added inline comments.


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Comment at: lib/Sema/SemaExpr.cpp:8808
+        Context.getTypeSize(pointerType) == 
+            Context.getTypeSize(IExp->getType()))
+      IsGNUIdiom = true;
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efriedma wrote:
> Please make sure you use exactly the same check in Sema and CodeGen (probably easiest to stick a helper into lib/AST/).
That's a good idea, but I'm not really familiar enough with the structure of clang to be sure I'm not doing it in a ham-fisted way.  Can you clarify?  Are you suggesting adding something like ASTContext::isPointeeTypeCharSize() and ASTContext::isIntegerTypePointerSize()?  Or maybe a single specialized function somewhere that does both checks like ASTContext::areOperandNullPointerArithmeticCompatible()?


https://reviews.llvm.org/D37042