diff --git a/clang-tools-extra/clang-tidy/ClangTidy.cpp b/clang-tools-extra/clang-tidy/ClangTidy.cpp --- a/clang-tools-extra/clang-tidy/ClangTidy.cpp +++ b/clang-tools-extra/clang-tidy/ClangTidy.cpp @@ -418,7 +418,8 @@ Preprocessor *PP = &Compiler.getPreprocessor(); Preprocessor *ModuleExpanderPP = PP; - if (Context.getLangOpts().Modules && OverlayFS != nullptr) { + if (Context.canEnableModuleHeadersParsing() && + Context.getLangOpts().Modules && OverlayFS != nullptr) { auto ModuleExpander = std::make_unique( &Compiler, OverlayFS); ModuleExpanderPP = ModuleExpander->getPreprocessor(); diff --git a/clang-tools-extra/clang-tidy/ClangTidyDiagnosticConsumer.h b/clang-tools-extra/clang-tidy/ClangTidyDiagnosticConsumer.h --- a/clang-tools-extra/clang-tidy/ClangTidyDiagnosticConsumer.h +++ b/clang-tools-extra/clang-tidy/ClangTidyDiagnosticConsumer.h @@ -70,7 +70,8 @@ public: /// Initializes \c ClangTidyContext instance. ClangTidyContext(std::unique_ptr OptionsProvider, - bool AllowEnablingAnalyzerAlphaCheckers = false); + bool AllowEnablingAnalyzerAlphaCheckers = false, + bool EnableModuleHeadersParsing = false); /// Sets the DiagnosticsEngine that diag() will emit diagnostics to. // FIXME: this is required initialization, and should be a constructor param. // Fix the context -> diag engine -> consumer -> context initialization cycle. @@ -198,6 +199,12 @@ return AllowEnablingAnalyzerAlphaCheckers; } + // This method determines whether preprocessor-level module header parsing is + // enabled using the `--experimental-enable-module-headers-parsing` option. + bool canEnableModuleHeadersParsing() const { + return EnableModuleHeadersParsing; + } + void setSelfContainedDiags(bool Value) { SelfContainedDiags = Value; } bool areDiagsSelfContained() const { return SelfContainedDiags; } @@ -245,6 +252,7 @@ std::string ProfilePrefix; bool AllowEnablingAnalyzerAlphaCheckers; + bool EnableModuleHeadersParsing; bool SelfContainedDiags; diff --git a/clang-tools-extra/clang-tidy/ClangTidyDiagnosticConsumer.cpp b/clang-tools-extra/clang-tidy/ClangTidyDiagnosticConsumer.cpp --- a/clang-tools-extra/clang-tidy/ClangTidyDiagnosticConsumer.cpp +++ b/clang-tools-extra/clang-tidy/ClangTidyDiagnosticConsumer.cpp @@ -161,10 +161,11 @@ ClangTidyContext::ClangTidyContext( std::unique_ptr OptionsProvider, - bool AllowEnablingAnalyzerAlphaCheckers) + bool AllowEnablingAnalyzerAlphaCheckers, bool EnableModuleHeadersParsing) : DiagEngine(nullptr), OptionsProvider(std::move(OptionsProvider)), Profile(false), AllowEnablingAnalyzerAlphaCheckers(AllowEnablingAnalyzerAlphaCheckers), + EnableModuleHeadersParsing(EnableModuleHeadersParsing), SelfContainedDiags(false) { // Before the first translation unit we can get errors related to command-line // parsing, use empty string for the file name in this case. diff --git a/clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp b/clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp --- a/clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp +++ b/clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp @@ -263,6 +263,17 @@ cl::init(false), cl::Hidden, cl::cat(ClangTidyCategory)); +static cl::opt EnableModuleHeadersParsing("enable-module-headers-parsing", + desc(R"( +Enables preprocessor-level module header parsing +for C++20 and above, empowering specific checks +to detect macro definitions within modules. This +feature may cause performance and parsing issues +and is therefore considered experimental. +)"), + cl::init(false), + cl::cat(ClangTidyCategory)); + static cl::opt ExportFixes("export-fixes", desc(R"( YAML file to store suggested fixes in. The stored fixes can be applied to the input source @@ -659,7 +670,8 @@ llvm::InitializeAllAsmParsers(); ClangTidyContext Context(std::move(OwningOptionsProvider), - AllowEnablingAnalyzerAlphaCheckers); + AllowEnablingAnalyzerAlphaCheckers, + EnableModuleHeadersParsing); std::vector Errors = runClangTidy(Context, OptionsParser->getCompilations(), PathList, BaseFS, FixNotes, EnableCheckProfile, ProfilePrefix); diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst --- a/clang-tools-extra/docs/ReleaseNotes.rst +++ b/clang-tools-extra/docs/ReleaseNotes.rst @@ -94,6 +94,20 @@ Improvements to clang-tidy -------------------------- +- Preprocessor-level module header parsing is now disabled by default due to + the problems it caused in C++20 and above, leading to performance and code + parsing issues regardless of whether modules were used or not. This change + will impact only the following checks: + :doc:`modernize-replace-disallow-copy-and-assign-macro + `, + :doc:`bugprone-reserved-identifier + `, and + :doc:`readability-identifier-naming + `. Those checks will no + longer see macros defined in modules. Users can still enable this + functionality using the newly added command line option + `--enable-module-headers-parsing`. + New checks ^^^^^^^^^^ diff --git a/clang-tools-extra/docs/clang-tidy/index.rst b/clang-tools-extra/docs/clang-tidy/index.rst --- a/clang-tools-extra/docs/clang-tidy/index.rst +++ b/clang-tools-extra/docs/clang-tidy/index.rst @@ -116,117 +116,122 @@ Generic Options: - --help - Display available options (--help-hidden for more) - --help-list - Display list of available options (--help-list-hidden for more) - --version - Display the version of this program + --help - Display available options (--help-hidden for more) + --help-list - Display list of available options (--help-list-hidden for more) + --version - Display the version of this program clang-tidy options: - --checks= - Comma-separated list of globs with optional '-' - prefix. Globs are processed in order of - appearance in the list. Globs without '-' - prefix add checks with matching names to the - set, globs with the '-' prefix remove checks - with matching names from the set of enabled - checks. This option's value is appended to the - value of the 'Checks' option in .clang-tidy - file, if any. - --config= - Specifies a configuration in YAML/JSON format: - -config="{Checks: '*', - CheckOptions: {x: y}}" - When the value is empty, clang-tidy will - attempt to find a file named .clang-tidy for - each source file in its parent directories. - --config-file= - Specify the path of .clang-tidy or custom config file: - e.g. --config-file=/some/path/myTidyConfigFile - This option internally works exactly the same way as - --config option after reading specified config file. - Use either --config-file or --config, not both. - --dump-config - Dumps configuration in the YAML format to - stdout. This option can be used along with a - file name (and '--' if the file is outside of a - project with configured compilation database). - The configuration used for this file will be - printed. - Use along with -checks=* to include - configuration of all checks. - --enable-check-profile - Enable per-check timing profiles, and print a - report to stderr. - --explain-config - For each enabled check explains, where it is - enabled, i.e. in clang-tidy binary, command - line or a specific configuration file. - --export-fixes= - YAML file to store suggested fixes in. The - stored fixes can be applied to the input source - code with clang-apply-replacements. - --extra-arg= - Additional argument to append to the compiler command line - --extra-arg-before= - Additional argument to prepend to the compiler command line - --fix - Apply suggested fixes. Without -fix-errors - clang-tidy will bail out if any compilation - errors were found. - --fix-errors - Apply suggested fixes even if compilation - errors were found. If compiler errors have - attached fix-its, clang-tidy will apply them as - well. - --fix-notes - If a warning has no fix, but a single fix can - be found through an associated diagnostic note, - apply the fix. - Specifying this flag will implicitly enable the - '--fix' flag. - --format-style= - Style for formatting code around applied fixes: - - 'none' (default) turns off formatting - - 'file' (literally 'file', not a placeholder) - uses .clang-format file in the closest parent - directory - - '{ }' specifies options inline, e.g. - -format-style='{BasedOnStyle: llvm, IndentWidth: 8}' - - 'llvm', 'google', 'webkit', 'mozilla' - See clang-format documentation for the up-to-date - information about formatting styles and options. - This option overrides the 'FormatStyle` option in - .clang-tidy file, if any. - --header-filter= - Regular expression matching the names of the - headers to output diagnostics from. Diagnostics - from the main file of each translation unit are - always displayed. - Can be used together with -line-filter. - This option overrides the 'HeaderFilterRegex' - option in .clang-tidy file, if any. - --line-filter= - List of files with line ranges to filter the - warnings. Can be used together with - -header-filter. The format of the list is a - JSON array of objects: - [ - {"name":"file1.cpp","lines":[[1,3],[5,7]]}, - {"name":"file2.h"} - ] - --list-checks - List all enabled checks and exit. Use with - -checks=* to list all available checks. - --load= - Load the specified plugin - -p - Build path - --quiet - Run clang-tidy in quiet mode. This suppresses - printing statistics about ignored warnings and - warnings treated as errors if the respective - options are specified. - --store-check-profile= - By default reports are printed in tabulated - format to stderr. When this option is passed, - these per-TU profiles are instead stored as JSON. - --system-headers - Display the errors from system headers. - This option overrides the 'SystemHeaders' option - in .clang-tidy file, if any. - --use-color - Use colors in diagnostics. If not set, colors - will be used if the terminal connected to - standard output supports colors. - This option overrides the 'UseColor' option in - .clang-tidy file, if any. - --verify-config - Check the config files to ensure each check and - option is recognized. - --vfsoverlay= - Overlay the virtual filesystem described by file - over the real file system. - --warnings-as-errors= - Upgrades warnings to errors. Same format as - '-checks'. - This option's value is appended to the value of - the 'WarningsAsErrors' option in .clang-tidy - file, if any. + --checks= - Comma-separated list of globs with optional '-' + prefix. Globs are processed in order of + appearance in the list. Globs without '-' + prefix add checks with matching names to the + set, globs with the '-' prefix remove checks + with matching names from the set of enabled + checks. This option's value is appended to the + value of the 'Checks' option in .clang-tidy + file, if any. + --config= - Specifies a configuration in YAML/JSON format: + -config="{Checks: '*', + CheckOptions: {x: y}}" + When the value is empty, clang-tidy will + attempt to find a file named .clang-tidy for + each source file in its parent directories. + --config-file= - Specify the path of .clang-tidy or custom config file: + e.g. --config-file=/some/path/myTidyConfigFile + This option internally works exactly the same way as + --config option after reading specified config file. + Use either --config-file or --config, not both. + --dump-config - Dumps configuration in the YAML format to + stdout. This option can be used along with a + file name (and '--' if the file is outside of a + project with configured compilation database). + The configuration used for this file will be + printed. + Use along with -checks=* to include + configuration of all checks. + --enable-check-profile - Enable per-check timing profiles, and print a + report to stderr. + --enable-module-headers-parsing - Enables preprocessor-level module header parsing + for C++20 and above, empowering specific checks + to detect macro definitions within modules. This + feature may cause performance and parsing issues + and is therefore considered experimental. + --explain-config - For each enabled check explains, where it is + enabled, i.e. in clang-tidy binary, command + line or a specific configuration file. + --export-fixes= - YAML file to store suggested fixes in. The + stored fixes can be applied to the input source + code with clang-apply-replacements. + --extra-arg= - Additional argument to append to the compiler command line + --extra-arg-before= - Additional argument to prepend to the compiler command line + --fix - Apply suggested fixes. Without -fix-errors + clang-tidy will bail out if any compilation + errors were found. + --fix-errors - Apply suggested fixes even if compilation + errors were found. If compiler errors have + attached fix-its, clang-tidy will apply them as + well. + --fix-notes - If a warning has no fix, but a single fix can + be found through an associated diagnostic note, + apply the fix. + Specifying this flag will implicitly enable the + '--fix' flag. + --format-style= - Style for formatting code around applied fixes: + - 'none' (default) turns off formatting + - 'file' (literally 'file', not a placeholder) + uses .clang-format file in the closest parent + directory + - '{ }' specifies options inline, e.g. + -format-style='{BasedOnStyle: llvm, IndentWidth: 8}' + - 'llvm', 'google', 'webkit', 'mozilla' + See clang-format documentation for the up-to-date + information about formatting styles and options. + This option overrides the 'FormatStyle` option in + .clang-tidy file, if any. + --header-filter= - Regular expression matching the names of the + headers to output diagnostics from. Diagnostics + from the main file of each translation unit are + always displayed. + Can be used together with -line-filter. + This option overrides the 'HeaderFilterRegex' + option in .clang-tidy file, if any. + --line-filter= - List of files with line ranges to filter the + warnings. Can be used together with + -header-filter. The format of the list is a + JSON array of objects: + [ + {"name":"file1.cpp","lines":[[1,3],[5,7]]}, + {"name":"file2.h"} + ] + --list-checks - List all enabled checks and exit. Use with + -checks=* to list all available checks. + --load= - Load the specified plugin + -p - Build path + --quiet - Run clang-tidy in quiet mode. This suppresses + printing statistics about ignored warnings and + warnings treated as errors if the respective + options are specified. + --store-check-profile= - By default reports are printed in tabulated + format to stderr. When this option is passed, + these per-TU profiles are instead stored as JSON. + --system-headers - Display the errors from system headers. + This option overrides the 'SystemHeaders' option + in .clang-tidy file, if any. + --use-color - Use colors in diagnostics. If not set, colors + will be used if the terminal connected to + standard output supports colors. + This option overrides the 'UseColor' option in + .clang-tidy file, if any. + --verify-config - Check the config files to ensure each check and + option is recognized. + --vfsoverlay= - Overlay the virtual filesystem described by file + over the real file system. + --warnings-as-errors= - Upgrades warnings to errors. Same format as + '-checks'. + This option's value is appended to the value of + the 'WarningsAsErrors' option in .clang-tidy + file, if any. -p is used to read a compile command database. diff --git a/clang-tools-extra/test/clang-tidy/infrastructure/expand-modular-headers-ppcallbacks.cpp b/clang-tools-extra/test/clang-tidy/infrastructure/expand-modular-headers-ppcallbacks.cpp --- a/clang-tools-extra/test/clang-tidy/infrastructure/expand-modular-headers-ppcallbacks.cpp +++ b/clang-tools-extra/test/clang-tidy/infrastructure/expand-modular-headers-ppcallbacks.cpp @@ -5,7 +5,7 @@ // RUN: %check_clang_tidy -std=c++11 %s readability-identifier-naming %t/without-modules -- \ // RUN: -config="CheckOptions: [{ \ // RUN: key: readability-identifier-naming.MacroDefinitionCase, value: UPPER_CASE }]" \ -// RUN: -header-filter=.* \ +// RUN: -header-filter=.* --enable-module-headers-parsing \ // RUN: -- -I %t/ // // RUN: rm -rf %t @@ -14,7 +14,7 @@ // RUN: %check_clang_tidy -std=c++17 %s readability-identifier-naming %t/without-modules -- \ // RUN: -config="CheckOptions: [{ \ // RUN: key: readability-identifier-naming.MacroDefinitionCase, value: UPPER_CASE }]" \ -// RUN: -header-filter=.* \ +// RUN: -header-filter=.* --enable-module-headers-parsing \ // RUN: -- -I %t/ // // Run clang-tidy on a file with modular includes: @@ -25,7 +25,7 @@ // RUN: %check_clang_tidy -std=c++11 %s readability-identifier-naming %t/with-modules -- \ // RUN: -config="CheckOptions: [{ \ // RUN: key: readability-identifier-naming.MacroDefinitionCase, value: UPPER_CASE }]" \ -// RUN: -header-filter=.* \ +// RUN: -header-filter=.* --enable-module-headers-parsing \ // RUN: -- -I %t/ \ // RUN: -fmodules -fimplicit-modules -fno-implicit-module-maps \ // RUN: -fmodule-map-file=%t/module.modulemap \ @@ -37,7 +37,7 @@ // RUN: %check_clang_tidy -std=c++17 %s readability-identifier-naming %t/with-modules -- \ // RUN: -config="CheckOptions: [{ \ // RUN: key: readability-identifier-naming.MacroDefinitionCase, value: UPPER_CASE }]" \ -// RUN: -header-filter=.* \ +// RUN: -header-filter=.* --enable-module-headers-parsing \ // RUN: -- -I %t/ \ // RUN: -fmodules -fimplicit-modules -fno-implicit-module-maps \ // RUN: -fmodule-map-file=%t/module.modulemap \