[modules] When a #include is mapped to a module import and appears somewhere
other than the top level, we issue an error. This breaks a fair amount of C++
code wrapping C libraries, where the C library is #included within a namespace
/ extern "C" combination, because the C library (probably) includes C++
standard library headers which may be within modules.
Without modules, this setup is harmless if (and *only* if) the corresponding
standard library module was already included outside the namespace, so
downgrade the error to a default-error extension in that case, so that it can
be selectively disabled for such misbehaving libraries.
llvm-svn: 253398
diff --git a/clang/test/Modules/auto-module-import.m b/clang/test/Modules/auto-module-import.m
index 76441fc..9a34c92 100644
--- a/clang/test/Modules/auto-module-import.m
+++ b/clang/test/Modules/auto-module-import.m
@@ -1,6 +1,7 @@
// RUN: rm -rf %t
// RUN: %clang_cc1 -Wauto-import -fmodules-cache-path=%t -fmodules -fimplicit-module-maps -F %S/Inputs %s -verify -DERRORS
// RUN: %clang_cc1 -Wauto-import -fmodules-cache-path=%t -fmodules -fimplicit-module-maps -F %S/Inputs %s -verify
+// RUN: %clang_cc1 -Wauto-import -fmodules-cache-path=%t -fmodules -fimplicit-module-maps -F %S/Inputs -xobjective-c++ %s -verify
//
// Test both with and without the declarations that refer to unimported
// entities. For error recovery, those cases implicitly trigger an import.
@@ -85,5 +86,16 @@
void includeNotAtTopLevel() { // expected-note {{function 'includeNotAtTopLevel' begins here}}
#include <NoUmbrella/A.h> // expected-warning {{treating #include as an import}} \
- expected-error {{import of module 'NoUmbrella.A' appears within function 'includeNotAtTopLevel'}}
+ expected-error {{redundant #include of module 'NoUmbrella.A' appears within function 'includeNotAtTopLevel'}}
}
+
+#ifdef __cplusplus
+namespace NS { // expected-note {{begins here}}
+#include <NoUmbrella/A.h> // expected-warning {{treating #include as an import}} \
+ expected-error {{redundant #include of module 'NoUmbrella.A' appears within namespace 'NS'}}
+}
+extern "C" { // expected-note {{begins here}}
+#include <NoUmbrella/A.h> // expected-warning {{treating #include as an import}} \
+ expected-error {{import of C++ module 'NoUmbrella.A' appears within extern "C"}}
+}
+#endif