[CodeComplete] Fix crash when completing ObjC block parameter with a broken type

Summary:
The fix isn't great, but it's hard to fix properly because the completion
code sensibly uses ParmVarDecl to represent parameters, but the AST-building
code sensibly doesn't synthesize them if the type is broken.
Also this case is apparently really rare, so it's probably not worth bending
over backwards for.

Reviewers: ilya-biryukov

Subscribers: javed.absar, kristof.beyls, arphaman, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D60258

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@357686 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Sema/SemaCodeComplete.cpp b/lib/Sema/SemaCodeComplete.cpp
index 2412d919ec967087f2278aa94f44734cf6e9aece..8d953308d818ae977db06561ef1843e99f826b09 100644 (file)
--- a/lib/Sema/SemaCodeComplete.cpp
+++ b/lib/Sema/SemaCodeComplete.cpp
@@ -2605,6 +2605,11 @@ static std::string
 FormatFunctionParameter(const PrintingPolicy &Policy, const ParmVarDecl *Param,
                         bool SuppressName = false, bool SuppressBlock = false,
                         Optional<ArrayRef<QualType>> ObjCSubsts = None) {
+  // Params are unavailable in FunctionTypeLoc if the FunctionType is invalid.
+  // It would be better to pass in the param Type, which is usually avaliable.
+  // But this case is rare, so just pretend we fell back to int as elsewhere.
+  if (!Param)
+    return "int";
   bool ObjCMethodParam = isa<ObjCMethodDecl>(Param->getDeclContext());
   if (Param->getType()->isDependentType() ||
       !Param->getType()->isBlockPointerType()) {

diff --git a/test/Index/complete-blocks.m b/test/Index/complete-blocks.m
index 046a08695d084ca0d85d17efc40f1b50b35c10cb..9c6c1cbf86db258cbd0e08fd795bc6f7bf1bbbf1 100644 (file)
--- a/test/Index/complete-blocks.m
+++ b/test/Index/complete-blocks.m
@@ -50,6 +50,15 @@ void test_f2(I1 *o) {
   [o method7:0];
 }
 
+// Crash regression test. Param info for broken function types isn't available.
+typedef UnresolvedType *(^XXX)(float);
+@interface Foo
+-(void) foo:(XXX)arg;
+@end
+void testUnresolved(Foo* f) {
+  [f foo:0];
+}
+
 // RUN: c-index-test -code-completion-at=%s:8:1 %s | FileCheck -check-prefix=CHECK-CC1 %s
 // CHECK-CC1: FunctionDecl:{ResultType void}{TypedText f}{LeftParen (}{Placeholder ^int(int x, int y)block}{RightParen )} (50)
 // CHECK-CC1: FunctionDecl:{ResultType void}{TypedText g}{LeftParen (}{Placeholder ^(float f, double d)b}{RightParen )} (50)
@@ -74,3 +83,6 @@ void test_f2(I1 *o) {
 // CHECK-CC7: FunctionDecl:{ResultType void}{TypedText f2}{LeftParen (}{Placeholder ^int(int x, int y)block}{RightParen )} (50)
 // RUN: c-index-test -code-completion-at=%s:50:6 %s | FileCheck -check-prefix=CHECK-CC8 %s
 // CHECK-CC8: ObjCInstanceMethodDecl:{ResultType id}{TypedText method7:}{Placeholder ^int(int x, int y)b} (35)
+
+// RUN: c-index-test -code-completion-at=%s:59:6 %s | FileCheck -check-prefix=CHECK-CC9 %s
+// CHECK-CC9: ObjCInstanceMethodDecl:{ResultType void}{TypedText foo:}{Placeholder ^int *(int)arg} (35)