[Frontend/Modules] Show diagnostics on prebuilt module configuration mismatch too

The current version only emits  the below error for a module (attempted to be loaded) from the `prebuilt-module-path`:

```
error: module file blabla.pcm cannot be loaded due to a configuration mismatch with the current compilation [-Wmodule-file-config-mismatch]
```

With this change, if the prebuilt module is used, we allow the proper diagnostic behind the configuration mismatch to be shown.

```
error: POSIX thread support was disabled in PCH file but is currently enabled
error: module file blabla.pcm cannot be loaded due to a configuration mismatch with the current compilation [-Wmodule-file-config-mismatch]
```

(A few lines later an error is emitted anyways, so there is no reason not to complain for configuration mismatches if a config mismatch is found and kills the build.)

Reviewed By: dblaikie

Tags: #clang

Differential Revision: https://reviews.llvm.org/D53334

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@346439 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Frontend/CompilerInstance.cpp b/lib/Frontend/CompilerInstance.cpp
index 719474dc765c380d9837cb0dfede0d36f7be55a4..be38c69235f44a7bcb8a06d13332ce20210e8d15 100644 (file)
--- a/lib/Frontend/CompilerInstance.cpp
+++ b/lib/Frontend/CompilerInstance.cpp
@@ -1727,7 +1727,9 @@ CompilerInstance::loadModule(SourceLocation ImportLoc,
     // module cache, we don't know how to rebuild modules.
     unsigned ARRFlags = Source == ModuleCache ?
                         ASTReader::ARR_OutOfDate | ASTReader::ARR_Missing :
-                        ASTReader::ARR_ConfigurationMismatch;
+                        Source == PrebuiltModulePath ?
+                            0 :
+                            ASTReader::ARR_ConfigurationMismatch;
     switch (ModuleManager->ReadAST(ModuleFileName,
                                    Source == PrebuiltModulePath
                                        ? serialization::MK_PrebuiltModule

diff --git a/test/Modules/mismatch-diagnostics.cpp b/test/Modules/mismatch-diagnostics.cpp
new file mode 100644 (file)
index 0000000..7754bce
--- /dev/null
+++ b/test/Modules/mismatch-diagnostics.cpp
@@ -0,0 +1,22 @@
+// RUN: rm -rf %t
+// RUN: mkdir -p %t/prebuilt_modules
+//
+// RUN: %clang_cc1 -triple %itanium_abi_triple                          \
+// RUN:     -fmodules-ts -fprebuilt-module-path=%t/prebuilt-modules     \
+// RUN:     -emit-module-interface -pthread -DBUILD_MODULE              \
+// RUN:     %s -o %t/prebuilt_modules/mismatching_module.pcm
+//
+// RUN: not %clang_cc1 -triple %itanium_abi_triple -fmodules-ts         \
+// RUN:     -fprebuilt-module-path=%t/prebuilt_modules -DCHECK_MISMATCH \
+// RUN:     %s 2>&1 | FileCheck %s
+
+#ifdef BUILD_MODULE
+export module mismatching_module;
+#endif
+
+#ifdef CHECK_MISMATCH
+import mismatching_module;
+// CHECK: error: POSIX thread support was enabled in PCH file but is currently disabled
+// CHECK-NEXT: module file {{.*}}/mismatching_module.pcm cannot be loaded due to a configuration mismatch with the current compilation
+#endif
+