llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang Author: Ivan Murashko (ivanmurashko) <details> <summary>Changes</summary> There were two diffs that introduced some options useful when you build modules externally and cannot rely on file modification time as the key for detecting input file changes: - [D67249](https://reviews.llvm.org/D67249) introduced the `-fmodules-validate-input-files-content` option, which allows the use of file content hash in addition to the modification time. - [D141632](https://reviews.llvm.org/D141632) propagated the use of `-fno-pch-timestamps` with Clang modules. There is a problem when the size of the input file (header) is not modified but the content is. In this case, Clang cannot detect the file change when the `-fno-pch-timestamps` option is used. The `-fmodules-validate-input-files-content` option should help, but there is an issue with its application: it's not applied when the modification time is stored as zero that is the case for `-fno-pch-timestamps`. The issue can be fixed using the same trick that was applied during the processing of `ForceCheckCXX20ModulesInputFiles`. The patch suggests the corresponding solution and includes a LIT test to verify it. --- Full diff: https://github.com/llvm/llvm-project/pull/90319.diff 2 Files Affected: - (modified) clang/lib/Serialization/ASTReader.cpp (+8) - (added) clang/test/Modules/implicit-module-no-timestamp.cpp (+33) ``````````diff diff --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp index 0ef57a3ea804ef..4609ca3e1428c8 100644 --- a/clang/lib/Serialization/ASTReader.cpp +++ b/clang/lib/Serialization/ASTReader.cpp @@ -2630,6 +2630,14 @@ InputFile ASTReader::getInputFile(ModuleFile &F, unsigned ID, bool Complain) { F.StandardCXXModule && FileChange.Kind == Change::None) FileChange = HasInputContentChanged(FileChange); + // When we have StoredTime equal to zero and ValidateASTInputFilesContent, + // it is better to check the content of the input files because we cannot rely + // on the file modification time, which will be the same (zero) for these + // files. + if (!StoredTime && ValidateASTInputFilesContent && + FileChange.Kind == Change::None) + FileChange = HasInputContentChanged(FileChange); + // For an overridden file, there is nothing to validate. if (!Overridden && FileChange.Kind != Change::None) { if (Complain && !Diags.isDiagnosticInFlight()) { diff --git a/clang/test/Modules/implicit-module-no-timestamp.cpp b/clang/test/Modules/implicit-module-no-timestamp.cpp new file mode 100644 index 00000000000000..457ad3c16e184c --- /dev/null +++ b/clang/test/Modules/implicit-module-no-timestamp.cpp @@ -0,0 +1,33 @@ +// RUN: rm -rf %t +// RUN: split-file %s %t +// RUN: cd %t +// +// RUN: cp a1.h a.h +// RUN: %clang -fmodules -fmodules-validate-input-files-content -Xclang -fno-pch-timestamp -fimplicit-modules -fmodule-map-file=module.modulemap -fsyntax-only -fmodules-cache-path=%t test1.cpp +// RUN: cp a2.h a.h +// RUN: %clang -fmodules -fmodules-validate-input-files-content -Xclang -fno-pch-timestamp -fimplicit-modules -fmodule-map-file=module.modulemap -fsyntax-only -fmodules-cache-path=%t test2.cpp + +//--- a1.h +#define FOO + +//--- a2.h +#define BAR + +//--- module.modulemap +module a { + header "a.h" +} + +//--- test1.cpp +#include "a.h" + +#ifndef FOO +#error foo +#endif + +//--- test2.cpp +#include "a.h" + +#ifndef BAR +#error bar +#endif `````````` </details> https://github.com/llvm/llvm-project/pull/90319 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
