[PCH] Fix a regression when PCH is used with -fmodules

Following up on r291465 after a regression in r276159. When we use
-fmodule-name=X while building a PCH, modular headers in X will be
textually included and the compiler knows that we are not building
module X, so don't serialize such headers in the PCH as being part of a
module, because at this point they are not.

This was causing subtle bugs and malformed AST crashes, for instance,
when using the PCH in subsequent compiler invocation with -fmodules, the
HFI for a modular header would map to the PCH, which would force a
module load of and unexistent module ID.

rdar://problem/30171164

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@294361 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 13 insertions, 0 deletions

diff --git a/test/Modules/invalid-pch-module-id.m b/test/Modules/invalid-pch-module-id.m
new file mode 100644
index 0000000000..34d9995cef
--- /dev/null
+++ b/test/Modules/invalid-pch-module-id.m
@@ -0,0 +1,13 @@
+// RUN: rm -rf %t.cache
+//
+// RUN: %clang_cc1 -x objective-c-header -fmodules -F%S/Inputs/invalid-module-id \
+// RUN:  -fmodule-implementation-of NC -fmodules-cache-path=%t.cache \
+// RUN:  -fimplicit-module-maps \
+// RUN:  -emit-pch %S/Inputs/invalid-module-id/NC-Prefix.pch -o %t.pch
+//
+// RUN: %clang_cc1 -x objective-c -fmodules -F%S/Inputs/invalid-module-id \
+// RUN:  -fmodule-implementation-of NC -fmodules-cache-path=%t.cache \
+// RUN:  -fimplicit-module-maps -include-pch %t.pch %s -fsyntax-only
+
+#import <NC/NULog.h>
+#import <NC/NUGeometry.h>