[modules] Add -fmodules-local-submodule-visibility flag.

This flag specifies that the normal visibility rules should be used even for
local submodules (submodules of the currently-being-built module). Thus names
will only be visible if a header / module that declares them has actually been
included / imported, and not merely because a submodule that happened to be
built earlier declared those names. This also removes the need to modularize
bottom-up: textually-included headers will be included into every submodule
that includes them, since their include guards will not leak between modules.

So far, this only governs visibility of macros, not of declarations, so is not
ready for real use yet.

llvm-svn: 236350

4 files changed, 55 insertions, 16 deletions

diff --git a/clang/test/Modules/macro-ambiguity.cpp b/clang/test/Modules/macro-ambiguity.cpp
index ea9e4f549f0..af43b35839a 100644
--- a/clang/test/Modules/macro-ambiguity.cpp
+++ b/clang/test/Modules/macro-ambiguity.cpp
@@ -57,6 +57,27 @@
 // RUN:   -fmodule-file=%t/c.pcm \
 // RUN:   -fmodule-file=%t/d.pcm \
 // RUN:   -Wambiguous-macro -verify macro-ambiguity.cpp
+//
+// RUN: %clang_cc1 -fmodules -x c++ -fmodules-cache-path=%t \
+// RUN:   -v -fmodules-local-submodule-visibility \
+// RUN:   -iquote Inputs/macro-ambiguity/a/quote \
+// RUN:   -isystem Inputs/macro-ambiguity/a/system \
+// RUN:   -iquote Inputs/macro-ambiguity/b/quote \
+// RUN:   -isystem Inputs/macro-ambiguity/b/system \
+// RUN:   -iquote Inputs/macro-ambiguity/c/quote \
+// RUN:   -isystem Inputs/macro-ambiguity/c/system \
+// RUN:   -iquote Inputs/macro-ambiguity/d/quote \
+// RUN:   -isystem Inputs/macro-ambiguity/d/system \
+// RUN:   -iquote Inputs/macro-ambiguity/e/quote \
+// RUN:   -isystem Inputs/macro-ambiguity/e/system \
+// RUN:   -fno-implicit-modules -fno-modules-implicit-maps \
+// RUN:   -fmodule-map-file-home-is-cwd \
+// RUN:   -fmodule-map-file=Inputs/macro-ambiguity/module.modulemap \
+// RUN:   -fmodule-file=%t/a.pcm \
+// RUN:   -fmodule-file=%t/b.pcm \
+// RUN:   -fmodule-file=%t/c.pcm \
+// RUN:   -fmodule-file=%t/d.pcm \
+// RUN:   -Wambiguous-macro -verify macro-ambiguity.cpp
 
 // Include the textual headers first to maximize the ways in which things can
 // become ambiguous.
diff --git a/clang/test/Modules/macro-reexport.cpp b/clang/test/Modules/macro-reexport.cpp
index 1df49b948d3..2be6f1532cb 100644
--- a/clang/test/Modules/macro-reexport.cpp
+++ b/clang/test/Modules/macro-reexport.cpp
@@ -7,6 +7,15 @@
 // RUN: %clang_cc1 -fsyntax-only -DD2 -I%S/Inputs/macro-reexport -fmodules %s -fmodules-cache-path=%t -verify
 // RUN: %clang_cc1 -fsyntax-only -DF1 -I%S/Inputs/macro-reexport %s -fmodules-cache-path=%t -verify
 // RUN: %clang_cc1 -fsyntax-only -DF1 -I%S/Inputs/macro-reexport -fmodules %s -fmodules-cache-path=%t -verify
+//
+// RUN: %clang_cc1 -fmodules-local-submodule-visibility -fsyntax-only -DC1 -I%S/Inputs/macro-reexport %s -fmodules-cache-path=%t -verify
+// RUN: %clang_cc1 -fmodules-local-submodule-visibility -fsyntax-only -DC1 -I%S/Inputs/macro-reexport -fmodules %s -fmodules-cache-path=%t -verify
+// RUN: %clang_cc1 -fmodules-local-submodule-visibility -fsyntax-only -DD1 -I%S/Inputs/macro-reexport %s -fmodules-cache-path=%t -verify
+// RUN: %clang_cc1 -fmodules-local-submodule-visibility -fsyntax-only -DD1 -I%S/Inputs/macro-reexport -fmodules %s -fmodules-cache-path=%t -verify
+// RUN: %clang_cc1 -fmodules-local-submodule-visibility -fsyntax-only -DD2 -I%S/Inputs/macro-reexport %s -fmodules-cache-path=%t -verify
+// RUN: %clang_cc1 -fmodules-local-submodule-visibility -fsyntax-only -DD2 -I%S/Inputs/macro-reexport -fmodules %s -fmodules-cache-path=%t -verify
+// RUN: %clang_cc1 -fmodules-local-submodule-visibility -fsyntax-only -DF1 -I%S/Inputs/macro-reexport %s -fmodules-cache-path=%t -verify
+// RUN: %clang_cc1 -fmodules-local-submodule-visibility -fsyntax-only -DF1 -I%S/Inputs/macro-reexport -fmodules %s -fmodules-cache-path=%t -verify
 
 #if defined(F1)
 #include "f1.h"
diff --git a/clang/test/Modules/macros.c b/clang/test/Modules/macros.c
index e367fb685b9..076166966b7 100644
--- a/clang/test/Modules/macros.c
+++ b/clang/test/Modules/macros.c
@@ -1,9 +1,6 @@
 // RUN: rm -rf %t
-// RUN: %clang_cc1 -fmodules -x objective-c -emit-module -fmodules-cache-path=%t -fmodule-name=macros_top %S/Inputs/module.map
-// RUN: %clang_cc1 -fmodules -x objective-c -emit-module -fmodules-cache-path=%t -fmodule-name=macros_left %S/Inputs/module.map
-// RUN: %clang_cc1 -fmodules -x objective-c -emit-module -fmodules-cache-path=%t -fmodule-name=macros_right %S/Inputs/module.map
-// RUN: %clang_cc1 -fmodules -x objective-c -emit-module -fmodules-cache-path=%t -fmodule-name=macros %S/Inputs/module.map
 // RUN: %clang_cc1 -fmodules -x objective-c -verify -fmodules-cache-path=%t -I %S/Inputs %s
+// RUN: %clang_cc1 -fmodules -DLOCAL_VISIBILITY -fmodules-local-submodule-visibility -x objective-c -verify -fmodules-cache-path=%t -I %S/Inputs %s
 // RUN: not %clang_cc1 -E -fmodules -x objective-c -fmodules-cache-path=%t -I %S/Inputs %s | FileCheck -check-prefix CHECK-PREPROCESSED %s
 // FIXME: When we have a syntax for modules in C, use that.
 // These notes come from headers in modules, and are bogus.
@@ -143,11 +140,20 @@ TOP_DEF_RIGHT_UNDEF *TDRUf() { return TDRUp; }
 
 int TOP_DEF_RIGHT_UNDEF; // ok, no longer defined
 
-// FIXME: When macros_right.undef is built, macros_top is visible because
-// the state from building macros_right leaks through, so macros_right.undef
-// undefines macros_top's macro.
-#ifdef TOP_RIGHT_UNDEF
-# error TOP_RIGHT_UNDEF should not be defined
+#ifdef LOCAL_VISIBILITY
+// TOP_RIGHT_UNDEF should not be undefined, because macros_right.undef does
+// not undefine macros_right's macro.
+# ifndef TOP_RIGHT_UNDEF
+#  error TOP_RIGHT_UNDEF should still be defined
+# endif
+#else
+// When macros_right.undef is built and local submodule visibility is not
+// enabled, macros_top is visible because the state from building
+// macros_right leaks through, so macros_right.undef undefines macros_top's
+// macro.
+# ifdef TOP_RIGHT_UNDEF
+#  error TOP_RIGHT_UNDEF should not be defined
+# endif
 #endif
 
 @import macros_other;
diff --git a/clang/test/Modules/macros2.c b/clang/test/Modules/macros2.c
index c4c8059011c..addb9b495cf 100644
--- a/clang/test/Modules/macros2.c
+++ b/clang/test/Modules/macros2.c
@@ -1,9 +1,6 @@
 // RUN: rm -rf %t
-// RUN: %clang_cc1 -fmodules -x objective-c -emit-module -fmodules-cache-path=%t -fmodule-name=macros_top %S/Inputs/module.map
-// RUN: %clang_cc1 -fmodules -x objective-c -emit-module -fmodules-cache-path=%t -fmodule-name=macros_left %S/Inputs/module.map
-// RUN: %clang_cc1 -fmodules -x objective-c -emit-module -fmodules-cache-path=%t -fmodule-name=macros_right %S/Inputs/module.map
-// RUN: %clang_cc1 -fmodules -x objective-c -emit-module -fmodules-cache-path=%t -fmodule-name=macros %S/Inputs/module.map
 // RUN: %clang_cc1 -fmodules -x objective-c -verify -fmodules-cache-path=%t -I %S/Inputs %s
+// RUN: %clang_cc1 -fmodules -fmodules-local-submodule-visibility -x objective-c -verify -fmodules-cache-path=%t -I %S/Inputs %s -DLOCAL_VISIBILITY
 
 // This test checks some of the same things as macros.c, but imports modules in
 // a different order.
@@ -49,9 +46,15 @@ void test() {
 
 @import macros_right.undef;
 
-// FIXME: See macros.c.
-#ifdef TOP_RIGHT_UNDEF
-# error TOP_RIGHT_UNDEF should not be defined
+// See macros.c.
+#ifdef LOCAL_VISIBILITY
+# ifndef TOP_RIGHT_UNDEF
+#  error TOP_RIGHT_UNDEF should still be defined
+# endif
+#else
+# ifdef TOP_RIGHT_UNDEF
+#  error TOP_RIGHT_UNDEF should not be defined
+# endif
 #endif
 
 #ifndef TOP_OTHER_UNDEF1