diff --git a/clang/docs/UsersManual.rst b/clang/docs/UsersManual.rst --- a/clang/docs/UsersManual.rst +++ b/clang/docs/UsersManual.rst @@ -904,6 +904,10 @@ CLANG_CONFIG_FILE_SYSTEM_DIR respectively. The first file found is used. It is an error if the required file cannot be found. +If no explicit configuration file is specified, Clang searches for a default +configuration file following the rules described in the next paragraphs. +To disable this behavior, `--no-default-config` flag can be used. + Another way to specify a configuration file is to encode it in executable name. For example, if the Clang executable is named `armv7l-clang` (it may be a symbolic link to `clang`), then Clang will search for file `armv7l.cfg` in the diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td --- a/clang/include/clang/Driver/Options.td +++ b/clang/include/clang/Driver/Options.td @@ -901,6 +901,8 @@ def compatibility__version : JoinedOrSeparate<["-"], "compatibility_version">; def config : Separate<["--"], "config">, Flags<[NoXarchOption]>, HelpText<"Specifies configuration file">; +def no_default_config : Flag<["--"], "no-default-config">, Flags<[NoXarchOption]>, + HelpText<"Disable loading default configuration files">; def config_system_dir_EQ : Joined<["--"], "config-system-dir=">, Flags<[NoXarchOption, HelpHidden]>, HelpText<"System directory for configuration files">; def config_user_dir_EQ : Joined<["--"], "config-user-dir=">, Flags<[NoXarchOption, HelpHidden]>, diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp --- a/clang/lib/Driver/Driver.cpp +++ b/clang/lib/Driver/Driver.cpp @@ -1024,11 +1024,14 @@ } } - // If config file is not specified explicitly, try to deduce configuration - // from executable name. For instance, an executable 'armv7l-clang' will - // search for config file 'armv7l-clang.cfg'. - if (CfgFileName.empty() && !ClangNameParts.TargetPrefix.empty()) - CfgFileName = ClangNameParts.TargetPrefix + '-' + ClangNameParts.ModeSuffix; + if (!(CLOptions && CLOptions->hasArg(options::OPT_no_default_config))) { + // If config file is not specified explicitly, try to deduce configuration + // from executable name. For instance, an executable 'armv7l-clang' will + // search for config file 'armv7l-clang.cfg'. + if (CfgFileName.empty() && !ClangNameParts.TargetPrefix.empty()) + CfgFileName = + ClangNameParts.TargetPrefix + '-' + ClangNameParts.ModeSuffix; + } if (CfgFileName.empty()) return false; diff --git a/clang/test/Driver/config-file3.c b/clang/test/Driver/config-file3.c --- a/clang/test/Driver/config-file3.c +++ b/clang/test/Driver/config-file3.c @@ -40,7 +40,13 @@ // RUN: %t/testdmode/qqq-clang-g++ --config-system-dir=%S/Inputs/config --config-user-dir= --config i386-qqq -c -no-canonical-prefixes -### %s 2>&1 | FileCheck %s -check-prefix CHECK-EXPLICIT // // CHECK-EXPLICIT: Configuration file: {{.*}}/Inputs/config/i386-qqq.cfg + +//--- --no-default-config disables config search. +// +// RUN: %t/testdmode/qqq-clang-g++ --config-system-dir= --config-user-dir=%t/testdmode --no-default-config -c -### %s 2>&1 | FileCheck %s -check-prefix NO-DEFAULT-CONFIG // +// NO-DEFAULT-CONFIG-NOT: Configuration file: + //--- Invocation qqq-clang-g++ tries to find config file qqq.cfg if qqq-clang-g++.cfg is not found. // // RUN: rm %t/testdmode/qqq-clang-g++.cfg