Implement return type deduction for lambdas per C++11

[expr.prim.lambda]p4, including the current suggested resolution of
core isue 975, which allows multiple return statements so long as the
types match. ExtWarn when user code is actually making use of this
extension.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@150168 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 8 insertions, 6 deletions

diff --git a/test/SemaCXX/lambda-expressions.cpp b/test/SemaCXX/lambda-expressions.cpp
index afdff999d4..1da57c6c72 100644
--- a/test/SemaCXX/lambda-expressions.cpp
+++ b/test/SemaCXX/lambda-expressions.cpp
@@ -34,12 +34,12 @@ namespace ReturnDeduction {
     [](){ return 1; }; 
     [](){ return 1; }; 
     [](){ return ({return 1; 1;}); }; 
-    [](){ return ({return 'c'; 1;}); }; // expected-error {{must match previous return type}}
+    [](){ return ({return 'c'; 1;}); }; // expected-error {{must match previous return type}} \
+    // expected-warning{{omitted result type}}
     []()->int{ return 'c'; return 1; }; 
     [](){ return 'c'; return 1; };  // expected-error {{must match previous return type}}
     []() { return; return (void)0; }; 
-    // FIXME: Need to check structure of lambda body 
-    [](){ return 1; return 1; }; 
+    [](){ return 1; return 1; }; // expected-warning{{omitted result type}}
   }
 }
 
@@ -76,9 +76,11 @@ namespace ImplicitCapture {
 
     struct G { G(); G(G&); int a; }; // expected-note 6 {{not viable}}
     G g;
-    [=]() { const G* gg = &g; return gg->a; }; 
-    [=]() { return [=]{ const G* gg = &g; return gg->a; }(); }; // expected-error {{no matching constructor for initialization of 'const ImplicitCapture::G'}} 
-    (void)^{ return [=]{ const G* gg = &g; return gg->a; }(); }; // expected-error 2 {{no matching constructor for initialization of 'const ImplicitCapture::G'}} 
+    [=]() { const G* gg = &g; return gg->a; }; // expected-warning{{omitted result type}}
+    [=]() { return [=]{ const G* gg = &g; return gg->a; }(); }; // expected-error {{no matching constructor for initialization of 'const ImplicitCapture::G'}}  \
+    // expected-warning{{omitted result type}}
+    (void)^{ return [=]{ const G* gg = &g; return gg->a; }(); }; // expected-error 2 {{no matching constructor for initialization of 'const ImplicitCapture::G'}}  \
+    // expected-warning{{omitted result type}}
 
     const int h = a; // expected-note {{declared}}
     []() { return h; }; // expected-error {{variable 'h' cannot be implicitly captured in a lambda with no capture-default specified}} expected-note {{lambda expression begins here}}