More forcibly resolve exception specifications when checking a function

redeclaration in C++1z mode. We need the exception specification in order for
the function's type to be complete.

llvm-svn: 285779

1 files changed, 9 insertions, 0 deletions

diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 319e63dbb18..1813aa0b648 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -2949,6 +2949,15 @@ bool Sema::MergeFunctionDecl(FunctionDecl *New, NamedDecl *&OldD,
     // but do not necessarily update the type of New.
     if (CheckEquivalentExceptionSpec(Old, New))
       return true;
+    // If exceptions are disabled, we might not have resolved the exception spec
+    // of one or both declarations. Do so now in C++1z, so that we can properly
+    // compare the types.
+    if (getLangOpts().CPlusPlus1z) {
+      for (QualType T : {Old->getType(), New->getType()})
+        if (auto *FPT = T->getAs<FunctionProtoType>())
+          if (isUnresolvedExceptionSpec(FPT->getExceptionSpecType()))
+            ResolveExceptionSpec(New->getLocation(), FPT);
+    }
     OldQType = Context.getCanonicalType(Old->getType());
     NewQType = Context.getCanonicalType(New->getType());