commit 60e141e1f87211ca831de6821003d80fe20a06f3
author Richard Smith <richard-llvm@metafoo.co.uk> Sat May 04 07:00:32 2013 +0000
committer Richard Smith <richard-llvm@metafoo.co.uk> Sat May 04 07:00:32 2013 +0000
tree 1d3062ca5c7b78cecae06c05ea1f90973d95d059
parent 82f145d4ed86d19cb2a1680cda53fdc39bb38eb6

Implement most of N3638 (return type deduction for normal functions).
Missing (somewhat ironically) is support for the new deduction rules
in lambda functions, plus PCH support for return type patching.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@181108 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Sema/SemaOverload.cpp

diff --git a/lib/Sema/SemaOverload.cpp b/lib/Sema/SemaOverload.cpp
index 480c4a0..e59c811 100644
--- a/lib/Sema/SemaOverload.cpp
+++ b/lib/Sema/SemaOverload.cpp
@@ -5726,6 +5726,14 @@
   if (!CandidateSet.isNewCandidate(Conversion))
     return;
 
+  // If the conversion function has an undeduced return type, trigger its
+  // deduction now.
+  if (getLangOpts().CPlusPlus1y && ConvType->isUndeducedType()) {
+    if (DeduceReturnType(Conversion, From->getExprLoc()))
+      return;
+    ConvType = Conversion->getConversionType().getNonReferenceType();
+  }
+
   // Overload resolution is always an unevaluated context.
   EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated);
 
@@ -9173,6 +9181,13 @@
           if (S.CheckCUDATarget(Caller, FunDecl))
             return false;
 
+      // If any candidate has a placeholder return type, trigger its deduction
+      // now.
+      if (S.getLangOpts().CPlusPlus1y &&
+          FunDecl->getResultType()->isUndeducedType() &&
+          S.DeduceReturnType(FunDecl, SourceExpr->getLocStart(), Complain))
+        return false;
+
       QualType ResultTy;
       if (Context.hasSameUnqualifiedType(TargetFunctionType, 
                                          FunDecl->getType()) ||
@@ -9439,6 +9454,11 @@
     if (FoundResult) *FoundResult = I.getPair();    
   }
 
+  if (Matched && getLangOpts().CPlusPlus1y &&
+      Matched->getResultType()->isUndeducedType() &&
+      DeduceReturnType(Matched, ovl->getExprLoc(), Complain))
+    return 0;
+
   return Matched;
 }