Revert r240335.

This failed to solve the problem it was aimed at, and introduced just as many
issues as it resolved. Realistically, we need to deal with the possibility that
multiple modules might define different internal linkage symbols with the same
name, and this isn't a problem unless two such symbols are simultaneously
visible.

The case where two modules define equivalent internal linkage symbols is
handled by r252063: if lookup finds multiple sufficiently-similar entities from
different modules, we just pick one of them as an extension (but we keep them
separate).

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@252957 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/clang/Basic/LangOptions.def b/include/clang/Basic/LangOptions.def
index 75816e9a2671f0a2268402a99d408a05f6df6932..fdf7e49499b8266e2fb3c197cef4fe0ec3d9f015 100644 (file)
--- a/include/clang/Basic/LangOptions.def
+++ b/include/clang/Basic/LangOptions.def
@@ -133,7 +133,6 @@ COMPATIBLE_LANGOPT(ModulesStrictDeclUse, 1, 0, "require declaration of module us
 BENIGN_LANGOPT(ModulesErrorRecovery, 1, 1, "automatically import modules as needed when performing error recovery")
 BENIGN_LANGOPT(ImplicitModules, 1, 1, "build modules that are not specified via -fmodule-file")
 COMPATIBLE_LANGOPT(ModulesLocalVisibility, 1, 0, "local submodule visibility")
-COMPATIBLE_LANGOPT(ModulesHideInternalLinkage, 1, 1, "hiding non-visible internal linkage declarations from redeclaration lookup")
 COMPATIBLE_LANGOPT(Optimize          , 1, 0, "__OPTIMIZE__ predefined macro")
 COMPATIBLE_LANGOPT(OptimizeSize      , 1, 0, "__OPTIMIZE_SIZE__ predefined macro")
 LANGOPT(Static            , 1, 0, "__STATIC__ predefined macro (as opposed to __DYNAMIC__)")

diff --git a/include/clang/Driver/CC1Options.td b/include/clang/Driver/CC1Options.td
index 24d32eea90dd04ac90c89797fac1984f59dd8ae9..56caea85b172ac70c7804c431893b49bb85f51ae 100644 (file)
--- a/include/clang/Driver/CC1Options.td
+++ b/include/clang/Driver/CC1Options.td
@@ -388,10 +388,6 @@ def fmodules_local_submodule_visibility :
 def fmodule_format_EQ : Joined<["-"], "fmodule-format=">,
   HelpText<"Select the container format for clang modules and PCH. "
            "Supported options are 'raw' and 'obj'.">;
-def fno_modules_hide_internal_linkage :
-  Flag<["-"], "fno-modules-hide-internal-linkage">,
-  HelpText<"Make all declarations visible to redeclaration lookup, "
-           "even if they have internal linkage.">;
 def ftest_module_file_extension_EQ :
   Joined<["-"], "ftest-module-file-extension=">,
   HelpText<"introduce a module file extension for testing purposes. "

diff --git a/include/clang/Sema/Sema.h b/include/clang/Sema/Sema.h
index c6506e44e3007c8328fee7dbf7dfea715c33d048..469c181f10567c30d830ea60229a44487abc2c40 100644 (file)
--- a/include/clang/Sema/Sema.h
+++ b/include/clang/Sema/Sema.h
@@ -277,9 +277,7 @@ class Sema {
     // it will keep having external linkage. If it has internal linkage, we
     // will not link it. Since it has no previous decls, it will remain
     // with internal linkage.
-    if (getLangOpts().ModulesHideInternalLinkage)
-      return isVisible(Old) || New->isExternallyVisible();
-    return true;
+    return isVisible(Old) || New->isExternallyVisible();
   }
 
 public:

diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index 7f401aa92573defd84bb46eac5da82d8807a7284..91917cf5100143cfe529ef9a888fac2cd51f8e98 100644 (file)
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -1627,8 +1627,6 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
       Args.hasArg(OPT_fmodules_decluse) || Opts.ModulesStrictDeclUse;
   Opts.ModulesLocalVisibility =
       Args.hasArg(OPT_fmodules_local_submodule_visibility);
-  Opts.ModulesHideInternalLinkage =
-      !Args.hasArg(OPT_fno_modules_hide_internal_linkage);
   Opts.ModulesSearchAll = Opts.Modules &&
     !Args.hasArg(OPT_fno_modules_search_all) &&
     Args.hasArg(OPT_fmodules_search_all);

diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 172952e8ca1f7dfa7bdb01d152b16530d16cd51e..728697e78f5d72ec10a051254eb8762dcc3f73db 100644 (file)
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -4822,7 +4822,6 @@ NamedDecl *Sema::HandleDeclarator(Scope *S, Declarator &D,
   // If we're hiding internal-linkage symbols in modules from redeclaration
   // lookup, let name lookup know.
   if ((getLangOpts().Modules || getLangOpts().ModulesLocalVisibility) &&
-      getLangOpts().ModulesHideInternalLinkage &&
       D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef)
     Previous.setAllowHiddenInternal(false);
 

diff --git a/test/Modules/submodules-merge-defs.cpp b/test/Modules/submodules-merge-defs.cpp
index 6a46e6dfa8a47b858df6d48d2f5d18bbcad2efcf..bb8e69367cafbd0436ed0de2895cad80e9c20411 100644 (file)
--- a/test/Modules/submodules-merge-defs.cpp
+++ b/test/Modules/submodules-merge-defs.cpp
@@ -3,7 +3,7 @@
 // RUN: %clang_cc1 -x c++ -std=c++11 -fmodules-cache-path=%t -fmodules -fimplicit-module-maps -I %S/Inputs/submodules-merge-defs %s -verify -fno-modules-error-recovery
 // RUN: %clang_cc1 -x c++ -std=c++11 -fmodules-cache-path=%t -fmodules -fimplicit-module-maps -I %S/Inputs/submodules-merge-defs %s -verify -fno-modules-error-recovery -fmodules-local-submodule-visibility -DTEXTUAL
 // RUN: %clang_cc1 -x c++ -std=c++11 -fmodules-cache-path=%t -fmodules -fimplicit-module-maps -I %S/Inputs/submodules-merge-defs %s -verify -fno-modules-error-recovery -fmodules-local-submodule-visibility
-// RUN: %clang_cc1 -x c++ -std=c++11 -fmodules-cache-path=%t -fimplicit-module-maps -I %S/Inputs/submodules-merge-defs %s -verify -fno-modules-error-recovery -fmodules-local-submodule-visibility -DTEXTUAL -DEARLY_INDIRECT_INCLUDE -fno-modules-hide-internal-linkage
+// RUN: %clang_cc1 -x c++ -std=c++11 -fmodules-cache-path=%t -fimplicit-module-maps -I %S/Inputs/submodules-merge-defs %s -verify -fno-modules-error-recovery -fmodules-local-submodule-visibility -DTEXTUAL -DEARLY_INDIRECT_INCLUDE
 // RUN: %clang_cc1 -x c++ -std=c++11 -fmodules-cache-path=%t -fmodules -fimplicit-module-maps -I %S/Inputs/submodules-merge-defs %s -verify -fno-modules-error-recovery -fmodules-local-submodule-visibility -fmodule-feature use_defs_twice -DIMPORT_USE_2
 
 // Trigger import of definitions, but don't make them visible.
@@ -111,4 +111,9 @@ MergeFunctionTemplateSpecializations::X<int>::Q<char> xiqc;
 #ifdef TEXTUAL
 #include "use-defs.h"
 void use_static_inline() { StaticInline::g({}); }
+#ifdef EARLY_INDIRECT_INCLUDE
+// expected-warning@-2 {{ambiguous use of internal linkage declaration 'g' defined in multiple modules}}
+// expected-note@defs.h:71 {{declared here in module 'redef'}}
+// expected-note@defs.h:71 {{declared here in module 'stuff.use'}}
+#endif
 #endif

diff --git a/test/Modules/using-decl.cpp b/test/Modules/using-decl.cpp
index 1677585ddafc106019546645ec3721e99ff56c87..b24593b5780261330d0fac5f0dce8656a4aefeaa 100644 (file)
--- a/test/Modules/using-decl.cpp
+++ b/test/Modules/using-decl.cpp
@@ -1,8 +1,6 @@
 // RUN: rm -rf %t
 // RUN: %clang_cc1 -x objective-c++ -std=c++11 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -I %S/Inputs %s -verify -DEARLY_IMPORT
 // RUN: %clang_cc1 -x objective-c++ -std=c++11 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -I %S/Inputs %s -verify -UEARLY_IMPORT
-// RUN: %clang_cc1 -x objective-c++ -std=c++11 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -I %S/Inputs %s -verify -DEARLY_IMPORT -fno-modules-hide-internal-linkage
-// RUN: %clang_cc1 -x objective-c++ -std=c++11 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -I %S/Inputs %s -verify -UEARLY_IMPORT -fno-modules-hide-internal-linkage
 // RUN: %clang_cc1 -x objective-c++ -std=c++11 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -I %S/Inputs %s -verify -DEARLY_IMPORT -fmodules-local-submodule-visibility
 // RUN: %clang_cc1 -x objective-c++ -std=c++11 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -I %S/Inputs %s -verify -UEARLY_IMPORT -fmodules-local-submodule-visibility