[PATCH] D33681: Allow function declaration with empty argument list.

[Alexey Bader via Phabricator via cfe-commits]

bader updated this revision to Diff 102319.
bader added a comment.

Update one more test missed in the first version of the patch.

Actually it looks like a bug in Parser.
Clang interprets following statement as variable declaration.

  extern pipe write_only int get_pipe();

So the type of the pipe element is function prototype: `int get_pipe()`.

If I understand the intention correctly, clang is expected to treat this expression function declaration with pipe return type, which elements are `int`.

Would it acceptable to commit this patch as is and file another bug on Parser?
I need more time to think how to resolve this ambiguity.


https://reviews.llvm.org/D33681

Files:
  lib/Sema/SemaType.cpp
  test/SemaOpenCL/function-no-args.cl
  test/SemaOpenCL/invalid-pipes-cl2.0.cl


Index: test/SemaOpenCL/invalid-pipes-cl2.0.cl
===================================================================
--- test/SemaOpenCL/invalid-pipes-cl2.0.cl
+++ test/SemaOpenCL/invalid-pipes-cl2.0.cl
@@ -3,7 +3,7 @@
 global pipe int gp;            // expected-error {{type '__global read_only pipe int' can only be used as a function parameter in OpenCL}}
 global reserve_id_t rid;          // expected-error {{the '__global reserve_id_t' type cannot be used to declare a program scope variable}}
 
-extern pipe write_only int get_pipe(); // expected-error {{type '__global write_only pipe int ()' can only be used as a function parameter in OpenCL}}
+extern pipe write_only int get_pipe(); // expected-error {{type '__global write_only pipe int (void)' can only be used as a function parameter in OpenCL}}
 
 kernel void test_invalid_reserved_id(reserve_id_t ID) { // expected-error {{'reserve_id_t' cannot be used as the type of a kernel parameter}}
 }
Index: test/SemaOpenCL/function-no-args.cl
===================================================================
--- /dev/null
+++ test/SemaOpenCL/function-no-args.cl
@@ -0,0 +1,9 @@
+// RUN: %clang_cc1 -verify -pedantic -fsyntax-only -cl-std=CL2.0 %s
+// expected-no-diagnostics
+
+global int gi;
+int my_func();
+int my_func() {
+  gi = 2;
+  return gi;
+}
Index: lib/Sema/SemaType.cpp
===================================================================
--- lib/Sema/SemaType.cpp
+++ lib/Sema/SemaType.cpp
@@ -4355,7 +4355,7 @@
 
       FunctionType::ExtInfo EI(getCCForDeclaratorChunk(S, D, FTI, chunkIndex));
 
-      if (!FTI.NumParams && !FTI.isVariadic && !LangOpts.CPlusPlus) {
+      if (!FTI.NumParams && !FTI.isVariadic && !LangOpts.CPlusPlus  && !LangOpts.OpenCL) {
         // Simple void foo(), where the incoming T is the result type.
         T = Context.getFunctionNoProtoType(T, EI);
       } else {


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