r207975 - Add -Wmodule-build to make it easy to see when modules are (re)built

[Ben Langmuir]

Author: benlangmuir
Date: Mon May  5 11:58:47 2014
New Revision: 207975

URL: http://llvm.org/viewvc/llvm-project?rev=207975&view=rev
Log:
Add -Wmodule-build to make it easy to see when modules are (re)built

Warning is default ignore, and not in -Wall.

Added:
    cfe/trunk/test/Modules/Wmodule-build.m
Modified:
    cfe/trunk/include/clang/Basic/DiagnosticFrontendKinds.td
    cfe/trunk/lib/Frontend/CompilerInstance.cpp

Modified: cfe/trunk/include/clang/Basic/DiagnosticFrontendKinds.td
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticFrontendKinds.td?rev=207975&r1=207974&r2=207975&view=diff
==============================================================================
--- cfe/trunk/include/clang/Basic/DiagnosticFrontendKinds.td (original)
+++ cfe/trunk/include/clang/Basic/DiagnosticFrontendKinds.td Mon May  5 11:58:47 2014
@@ -167,6 +167,8 @@ def warn_module_config_macro_undef : War
   InGroup<ConfigMacros>;
 def note_module_def_undef_here : Note<
   "macro was %select{defined|#undef'd}0 here">;
+def warn_module_build : Warning<"building module '%0' as '%1'">,
+  InGroup<DiagGroup<"module-build">>, DefaultIgnore;
 
 def err_missing_vfs_overlay_file : Error<
   "virtual filesystem overlay file '%0' not found">, DefaultFatal;

Modified: cfe/trunk/lib/Frontend/CompilerInstance.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Frontend/CompilerInstance.cpp?rev=207975&r1=207974&r2=207975&view=diff
==============================================================================
--- cfe/trunk/lib/Frontend/CompilerInstance.cpp (original)
+++ cfe/trunk/lib/Frontend/CompilerInstance.cpp Mon May  5 11:58:47 2014
@@ -1219,6 +1219,9 @@ CompilerInstance::loadModule(SourceLocat
         return ModuleLoadResult();
       }
 
+      getDiagnostics().Report(ImportLoc, diag::warn_module_build)
+          << ModuleName << ModuleFileName;
+
       // Check whether we have already attempted to build this module (but
       // failed).
       if (getPreprocessorOpts().FailedModules &&

Added: cfe/trunk/test/Modules/Wmodule-build.m
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Modules/Wmodule-build.m?rev=207975&view=auto
==============================================================================
--- cfe/trunk/test/Modules/Wmodule-build.m (added)
+++ cfe/trunk/test/Modules/Wmodule-build.m Mon May  5 11:58:47 2014
@@ -0,0 +1,22 @@
+// REQUIRES: shell
+// RUN: rm -rf %t
+// RUN: mkdir %t
+// RUN: echo '// A' > %t/A.h
+// RUN: echo '// B' > %t/B.h
+// RUN: echo 'module A { header "A.h" }' > %t/module.modulemap
+// RUN: echo 'module B { header "B.h" }' >> %t/module.modulemap
+
+// RUN: %clang_cc1 -fmodules -fmodules-cache-path=%t -fsyntax-only %s -verify \
+// RUN:            -I %t -Wmodule-build
+
+ at import A; // expected-warning{{building module 'A' as}}
+ at import B; // expected-warning{{building module 'B' as}}
+ at import A; // no diagnostic
+ at import B; // no diagnostic
+
+// RUN: echo ' ' >> %t/B.h
+// RUN: %clang_cc1 -fmodules -fmodules-cache-path=%t -fsyntax-only %s -I %t \
+// RUN:            -Wmodule-build 2>&1 | FileCheck %s
+
+// CHECK-NOT: building module 'A'
+// CHECK: building module 'B'