r291963 - [clang] Emit `diagnose_if` warnings from system headers

[Eric Fiselier via cfe-commits]

Author: ericwf
Date: Fri Jan 13 16:11:40 2017
New Revision: 291963

URL: http://llvm.org/viewvc/llvm-project?rev=291963&view=rev
Log:
[clang] Emit `diagnose_if` warnings from system headers

Summary: In order for libc++ to meaningfully use `diagnose_if` warnings they need to be emitted from system headers by default. This patch changes the `diagnose_if` warning diagnostic to be shown in system headers.

Reviewers: george.burgess.iv, rsmith, aaron.ballman

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D28703

Added:
    cfe/trunk/test/Sema/Inputs/diagnose-if-warn-system-header.h
Modified:
    cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
    cfe/trunk/test/Sema/diagnose_if.c

Modified: cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td?rev=291963&r1=291962&r2=291963&view=diff
==============================================================================
--- cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td (original)
+++ cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td Fri Jan 13 16:11:40 2017
@@ -3380,7 +3380,8 @@ def note_ovl_candidate_has_pass_object_s
     "candidate address cannot be taken because parameter %0 has "
     "pass_object_size attribute">;
 def err_diagnose_if_succeeded : Error<"%0">;
-def warn_diagnose_if_succeeded : Warning<"%0">, InGroup<UserDefinedWarnings>;
+def warn_diagnose_if_succeeded : Warning<"%0">, InGroup<UserDefinedWarnings>,
+    ShowInSystemHeader;
 def note_ovl_candidate_disabled_by_function_cond_attr : Note<
     "candidate disabled: %0">;
 def note_ovl_candidate_disabled_by_extension : Note<

Added: cfe/trunk/test/Sema/Inputs/diagnose-if-warn-system-header.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Sema/Inputs/diagnose-if-warn-system-header.h?rev=291963&view=auto
==============================================================================
--- cfe/trunk/test/Sema/Inputs/diagnose-if-warn-system-header.h (added)
+++ cfe/trunk/test/Sema/Inputs/diagnose-if-warn-system-header.h Fri Jan 13 16:11:40 2017
@@ -0,0 +1,11 @@
+#pragma GCC system_header
+
+inline int system_header_func(int x)
+  __attribute__((diagnose_if(x == x, "system header warning", "warning"))) // expected-note {{from 'diagnose_if' attribute}}
+{
+  return 0;
+}
+
+void test_system_header() {
+  system_header_func(0); // expected-warning {{system header warning}}
+}

Modified: cfe/trunk/test/Sema/diagnose_if.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Sema/diagnose_if.c?rev=291963&r1=291962&r2=291963&view=diff
==============================================================================
--- cfe/trunk/test/Sema/diagnose_if.c (original)
+++ cfe/trunk/test/Sema/diagnose_if.c Fri Jan 13 16:11:40 2017
@@ -150,3 +150,6 @@ void alwaysWarnWithArg(int a) _diagnose_
 void runAlwaysWarnWithArg(int a) {
   alwaysWarnWithArg(a); // expected-warning{{alwaysWarn}}
 }
+
+// Test that diagnose_if warnings generated in system headers are not ignored.
+#include "Inputs/diagnose-if-warn-system-header.h"