r239639 - [ms] Don't try to delay lookup for failures in SFINAE context (PR23823)

[Hans Wennborg]

Author: hans
Date: Fri Jun 12 16:23:23 2015
New Revision: 239639

URL: http://llvm.org/viewvc/llvm-project?rev=239639&view=rev
Log:
[ms] Don't try to delay lookup for failures in SFINAE context (PR23823)

The underlying problem in PR23823 already existed before my recent change
in r239558, but that change made it worse (failing not only for undeclared
symbols, but also failed overload resolution). This makes Clang not try to
delay the lookup in SFINAE context. I assume no current code is relying on
SFINAE working with lookups that need to be delayed, because that never
seems to have worked.

Differential Revision: http://reviews.llvm.org/D10417

Modified:
    cfe/trunk/lib/Sema/SemaOverload.cpp
    cfe/trunk/test/SemaTemplate/ms-lookup-template-base-classes.cpp

Modified: cfe/trunk/lib/Sema/SemaOverload.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaOverload.cpp?rev=239639&r1=239638&r2=239639&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaOverload.cpp (original)
+++ cfe/trunk/lib/Sema/SemaOverload.cpp Fri Jun 12 16:23:23 2015
@@ -10750,7 +10750,8 @@ bool Sema::buildOverloadedCallSet(Scope
   // functions, including those from argument-dependent lookup.
   AddOverloadedCallCandidates(ULE, Args, *CandidateSet);
 
-  if (getLangOpts().MSVCCompat && CurContext->isDependentContext() &&
+  if (getLangOpts().MSVCCompat &&
+      CurContext->isDependentContext() && !isSFINAEContext() &&
       (isa<FunctionDecl>(CurContext) || isa<CXXRecordDecl>(CurContext))) {
 
     OverloadCandidateSet::iterator Best;

Modified: cfe/trunk/test/SemaTemplate/ms-lookup-template-base-classes.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaTemplate/ms-lookup-template-base-classes.cpp?rev=239639&r1=239638&r2=239639&view=diff
==============================================================================
--- cfe/trunk/test/SemaTemplate/ms-lookup-template-base-classes.cpp (original)
+++ cfe/trunk/test/SemaTemplate/ms-lookup-template-base-classes.cpp Fri Jun 12 16:23:23 2015
@@ -563,3 +563,13 @@ void test() {
   x.member(); // expected-note{{requested here}}
 };
 }
+
+namespace PR23823 {
+// Don't delay lookup in SFINAE context.
+template <typename T> decltype(g(T())) check(); // expected-note{{candidate template ignored: substitution failure [with T = int]: use of undeclared identifier 'g'}}
+decltype(check<int>()) x; // expected-error{{no matching function for call to 'check'}}
+
+void h();
+template <typename T> decltype(h(T())) check2(); // expected-note{{candidate template ignored: substitution failure [with T = int]: no matching function for call to 'h'}}
+decltype(check2<int>()) y; // expected-error{{no matching function for call to 'check2'}}
+}