Author: Chuanqi Xu Date: 2024-06-24T19:03:31+08:00 New Revision: cc4ec6daf0d4f43110e8220d542c1155b8c1ef51
URL: https://github.com/llvm/llvm-project/commit/cc4ec6daf0d4f43110e8220d542c1155b8c1ef51 DIFF: https://github.com/llvm/llvm-project/commit/cc4ec6daf0d4f43110e8220d542c1155b8c1ef51.diff LOG: [C++20] [Modules] Diagnose redeclarations from different modules [basic.link]/p10: > If two declarations of an entity are attached to different modules, > the program is ill-formed But we only implemented the check for ODR. In this patch, we tried to diagnose the redeclarations from different modules. Added: clang/test/Modules/same-decl-in-different-modules.cppm Modified: clang/include/clang/Basic/DiagnosticSemaKinds.td clang/lib/Serialization/ASTReaderDecl.cpp clang/test/Modules/no-eager-load.cppm Removed: ################################################################################ diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td index f323d1c6eaf1b..134a4e4d547dd 100644 --- a/clang/include/clang/Basic/DiagnosticSemaKinds.td +++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td @@ -6075,6 +6075,9 @@ def err_thread_thread_ diff erent_kind : Error< def err_mismatched_owning_module : Error< "declaration of %0 in %select{the global module|module %2}1 follows " "declaration in %select{the global module|module %4}3">; +def err_multiple_decl_in_ diff erent_modules : Error< + "declaration %0 attached to named module '%1' can't be attached to " + "other modules">; def err_redefinition_ diff erent_type : Error< "redefinition of %0 with a diff erent type% diff {: $ vs $|}1,2">; def err_redefinition_ diff erent_kind : Error< diff --git a/clang/lib/Serialization/ASTReaderDecl.cpp b/clang/lib/Serialization/ASTReaderDecl.cpp index 4b8b515c02c70..6afb18f932e72 100644 --- a/clang/lib/Serialization/ASTReaderDecl.cpp +++ b/clang/lib/Serialization/ASTReaderDecl.cpp @@ -3723,6 +3723,23 @@ void ASTDeclReader::attachPreviousDecl(ASTReader &Reader, Decl *D, #include "clang/AST/DeclNodes.inc" } + // [basic.link]/p10: + // If two declarations of an entity are attached to diff erent modules, + // the program is ill-formed; + // + // FIXME: Get rid of the enumeration of decl types once we have an appropriate + // abstract for decls of an entity. e.g., the namespace decl and using decl + // doesn't introduce an entity. + if (Module *M = Previous->getOwningModule(); + M && M->isNamedModule() && + isa<VarDecl, FunctionDecl, TagDecl, RedeclarableTemplateDecl>(Previous) && + !Reader.getContext().isInSameModule(M, D->getOwningModule())) { + Reader.Diag(Previous->getLocation(), + diag::err_multiple_decl_in_ diff erent_modules) + << cast<NamedDecl>(Previous) << M->Name; + Reader.Diag(D->getLocation(), diag::note_also_found); + } + // If the declaration was visible in one module, a redeclaration of it in // another module remains visible even if it wouldn't be visible by itself. // diff --git a/clang/test/Modules/no-eager-load.cppm b/clang/test/Modules/no-eager-load.cppm index 8a2c7656bca2b..c9eddaaed1555 100644 --- a/clang/test/Modules/no-eager-load.cppm +++ b/clang/test/Modules/no-eager-load.cppm @@ -44,6 +44,9 @@ void use() { // expected-note@* {{but in 'a' found a diff erent body}} } +// expected-er...@a.cppm:* {{declaration 'foo' attached to named module 'a' can't be attached to other modules}} +// expected-n...@b.cppm:* {{}} + //--- h.cppm export module h; export import a; @@ -55,3 +58,6 @@ void use() { foo(); // expected-error@* {{'foo' has diff erent definitions in diff erent modules;}} // expected-note@* {{but in 'a' found a diff erent body}} } + +// expected-er...@a.cppm:* {{declaration 'foo' attached to named module 'a' can't be attached to other modules}} +// expected-n...@b.cppm:* {{}} diff --git a/clang/test/Modules/same-decl-in- diff erent-modules.cppm b/clang/test/Modules/same-decl-in- diff erent-modules.cppm new file mode 100644 index 0000000000000..2e8e90f7cd8e9 --- /dev/null +++ b/clang/test/Modules/same-decl-in- diff erent-modules.cppm @@ -0,0 +1,42 @@ +// RUN: rm -rf %t +// RUN: mkdir %t +// RUN: split-file %s %t +// +// RUN: %clang_cc1 -std=c++20 %t/mod1.cppm -emit-module-interface -o %t/mod1.pcm +// RUN: %clang_cc1 -std=c++20 %t/mod2.cppm -emit-module-interface -o %t/mod2.pcm +// RUN: %clang_cc1 -std=c++20 %t/test.cc -fprebuilt-module-path=%t -fsyntax-only -verify + +//--- mod1.cppm +export module mod1; +export int v; +export void func(); +export class A {}; +export template <class C> +struct S {}; + +//--- mod2.cppm +export module mod2; +export int v; +export void func(); +export class A; +export template <class C> +struct S {}; + +//--- test.cc +import mod1; +import mod2; +void test() { + int value = v; + func(); + A a; + S<int> s; +} + +// expected-er...@mod1.cppm:* {{declaration 'v' attached to named module 'mod1' can't be attached to other modules}} +// expected-n...@mod2.cppm:* {{}} +// expected-er...@mod1.cppm:* {{declaration 'func' attached to named module 'mod1' can't be attached to other modules}} +// expected-n...@mod2.cppm:* {{}} +// expected-er...@mod1.cppm:* {{declaration 'A' attached to named module 'mod1' can't be attached to other modules}} +// expected-n...@mod2.cppm:* {{}} +// expected-er...@mod1.cppm:* 1+{{declaration 'S' attached to named module 'mod1' can't be attached to other modules}} +// expected-n...@mod2.cppm:* 1+{{}} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
