[clang] 031738a - [AST][RecoveryExpr] Don't preserve the return type if the FunctionDecl is invalid.

[Haojian Wu via cfe-commits]

Author: Haojian Wu
Date: 2020-08-11T13:49:57+02:00
New Revision: 031738a5611843674d5f739e739e8a386d5e741b

URL: https://github.com/llvm/llvm-project/commit/031738a5611843674d5f739e739e8a386d5e741b
DIFF: https://github.com/llvm/llvm-project/commit/031738a5611843674d5f739e739e8a386d5e741b.diff

LOG: [AST][RecoveryExpr] Don't preserve the return type if the FunctionDecl is invalid.

If a functionDecl is invalid (e.g. return type cannot be formed), int is
use as he fallback type, which may lead to some bogus diagnostics.

Reviewed By: sammccall

Differential Revision: https://reviews.llvm.org/D85714

Added: 
    

Modified: 
    clang/lib/Sema/SemaOverload.cpp
    clang/test/SemaCXX/recovery-expr-type.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp
index 5a20a7990c3b..bcf6aa7a310e 100644
--- a/clang/lib/Sema/SemaOverload.cpp
+++ b/clang/lib/Sema/SemaOverload.cpp
@@ -12821,6 +12821,8 @@ static QualType chooseRecoveryType(OverloadCandidateSet &CS,
   auto ConsiderCandidate = [&](const OverloadCandidate &Candidate) {
     if (!Candidate.Function)
       return;
+    if (Candidate.Function->isInvalidDecl())
+      return;
     QualType T = Candidate.Function->getReturnType();
     if (T.isNull())
       return;

diff  --git a/clang/test/SemaCXX/recovery-expr-type.cpp b/clang/test/SemaCXX/recovery-expr-type.cpp
index 6cd79326e8c3..2ce47f2f8efc 100644
--- a/clang/test/SemaCXX/recovery-expr-type.cpp
+++ b/clang/test/SemaCXX/recovery-expr-type.cpp
@@ -68,3 +68,10 @@ namespace test4 {
 int &&f(int);  // expected-note {{candidate function not viable}}
 int &&k = f(); // expected-error {{no matching function for call}}
 }
+
+// verify that "type 'double' cannot bind to a value of unrelated type 'int'" diagnostic is suppressed.
+namespace test5 {
+  template<typename T> using U = T; // expected-note {{template parameter is declared here}}
+  template<typename...Ts> U<Ts...>& f(); // expected-error {{pack expansion used as argument for non-pack parameter of alias template}}
+  double &s1 = f(); // expected-error {{no matching function}}
+}