[PATCH] D41880: Adding nocf_check attribute for cf-protection fine tuning

[Aaron Ballman via Phabricator via llvm-commits]

aaron.ballman added inline comments.


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Comment at: lib/Sema/SemaDeclAttr.cpp:1990
 
-bool Sema::CheckNoReturnAttr(const AttributeList &Attrs) {
-  if (!checkAttributeNumArgs(*this, Attrs, 0)) {
-    Attrs.setInvalid();
+static void handleNoCfCheckAttr(Sema &S, Decl *D, const AttributeList &attr) {
+  if (S.CheckAttrTarget(attr) || S.CheckAttrNoArgs(attr))
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oren_ben_simhon wrote:
> aaron.ballman wrote:
> > aaron.ballman wrote:
> > > `attr` doesn't follow the proper naming conventions.
> > Please don't name the parameter variable after a type -- that can confuse some editors.
> I am following the same convention that other functions are using.
> I am following the same convention that other functions are using.

They're doing it wrong. I can clean those up in a separate patch.


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Comment at: test/Sema/attr-nocf_check.c:18-20
+  FuncPointerWithNoCfCheck fNoCfCheck = f; // no-warning
+  (*fNoCfCheck)();                       // no-warning
+  f = fNoCfCheck;                        // no-warning
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oren_ben_simhon wrote:
> aaron.ballman wrote:
> > These are an error in GCC and I think we should match that behavior. https://godbolt.org/g/r3pf4X
> I will create a warning however in LLVM we don't create an error upon incompatible pointer due to function attribute types.
It should be an error -- Clang does error on this sort of thing when appropriate (which I believe it is, here). For instance, calling convention attributes do this: https://godbolt.org/g/mkTGLg


Repository:
  rL LLVM

https://reviews.llvm.org/D41880