Warn on va_start() when called with a reference parameter.
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2005/n1905.pdf 18.7p3
explicitly calls this (and some other things) out as undefined.
Also move 2 other existing warnings behind the new -Wvarargs flag.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@182694 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaChecking.cpp b/lib/Sema/SemaChecking.cpp
index 3471c00..cdc546c 100644
--- a/lib/Sema/SemaChecking.cpp
+++ b/lib/Sema/SemaChecking.cpp
@@ -1355,6 +1355,11 @@
bool SecondArgIsLastNamedArgument = false;
const Expr *Arg = TheCall->getArg(1)->IgnoreParenCasts();
+ // These are valid if SecondArgIsLastNamedArgument is false after the next
+ // block.
+ QualType Type;
+ SourceLocation ParamLoc;
+
if (const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(Arg)) {
if (const ParmVarDecl *PV = dyn_cast<ParmVarDecl>(DR->getDecl())) {
// FIXME: This isn't correct for methods (results in bogus warning).
@@ -1367,12 +1372,21 @@
else
LastArg = *(getCurMethodDecl()->param_end()-1);
SecondArgIsLastNamedArgument = PV == LastArg;
+
+ Type = PV->getType();
+ ParamLoc = PV->getLocation();
}
}
if (!SecondArgIsLastNamedArgument)
Diag(TheCall->getArg(1)->getLocStart(),
diag::warn_second_parameter_of_va_start_not_last_named_argument);
+ else if (Type->isReferenceType()) {
+ Diag(Arg->getLocStart(),
+ diag::warn_va_start_of_reference_type_is_undefined);
+ Diag(ParamLoc, diag::note_parameter_type) << Type;
+ }
+
return false;
}