[PATCH] D19312: Warn about UB at member function calls from base class ctor initializers.

[Artem Dergachev via Phabricator via cfe-commits]

NoQ added a comment.

Sorry, couldn't help it. This patch looks so useful and so lonely :)



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Comment at: include/clang/Basic/DiagnosticSemaKinds.td:6782
+def warn_member_call_in_ctor_init : Warning<
+  "member function call %0 in ctor-initializer for base class %1 results in "
+  "undefined behavior">,
----------------
I don't see these things referred to as "ctor-initializers" in other diagnostics. I'd rather say "initializer".

Also "has undefined behavior" is shorter and nicer.


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Comment at: lib/Sema/SemaDeclCXX.cpp:2295
+    // or 0 if the current CXXCtorInitializer isn't initializing a base class.
+    const Type *CurrentBaseClass;
 
----------------
I'd be scared not to initialize this variable to null.

Also, this visitor scans only one constructor throughout its lifetime, right?


================
Comment at: lib/Sema/SemaDeclCXX.cpp:2588-2589
+        // is undefined behavior.
+        // As getImplicitObjectArgument() returns 0 for member pointer
+        // calls we use dyn_cast_or_null instead of isa.
+        if (dyn_cast_or_null<CXXThisExpr>(E->getImplicitObjectArgument())) {
----------------
Ugh.

This is worth a test case!


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D19312/new/

https://reviews.llvm.org/D19312