diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp --- a/clang/lib/Driver/ToolChains/Clang.cpp +++ b/clang/lib/Driver/ToolChains/Clang.cpp @@ -3798,6 +3798,10 @@ Args.ClaimAllArgs(options::OPT_fmodules_disable_diagnostic_validation); } + // Claim `-fmodule-output` and `-fmodule-output=` to avoid unused warnings. + Args.ClaimAllArgs(options::OPT_fmodule_output); + Args.ClaimAllArgs(options::OPT_fmodule_output_EQ); + return HaveModules; } diff --git a/clang/test/Driver/module-output.cppm b/clang/test/Driver/module-output.cppm --- a/clang/test/Driver/module-output.cppm +++ b/clang/test/Driver/module-output.cppm @@ -27,6 +27,9 @@ // in the comamnd line. // RUN: %clang -std=c++20 %t/Hello.cppm -fmodule-output=%t/pcm/Hello.pcm -o %t/Hello.o \ // RUN: -c -### 2>&1 | FileCheck %t/Hello.cppm --check-prefix=CHECK-SPECIFIED +// +// RUN: %clang -std=c++20 %t/Hello.cppm -fmodule-output=%t/Hello.pcm -fmodule-output -c -fsyntax-only \ +// RUN: -### 2>&1 | FileCheck %t/Hello.cppm --check-prefix=CHECK-NOT-USED //--- Hello.cppm export module Hello; @@ -39,6 +42,11 @@ // CHECK-SPECIFIED: "-emit-module-interface" {{.*}}"-main-file-name" "Hello.cppm" {{.*}}"-o" "{{.*}}/pcm/Hello.pcm" "-x" "c++" "{{.*}}/Hello.cppm" // CHECK-SPECIFIED: "-emit-obj" {{.*}}"-main-file-name" "Hello.cppm" {{.*}}"-o" "{{.*}}/Hello.o" "-x" "pcm" "{{.*}}/pcm/Hello.pcm" +// CHECK-NOT-USED-NOT: warning: argument unused during compilation: '-fmodule-output' +// CHECK-NOT-USED-NOT: warning: argument unused during compilation: '-fmodule-output=Hello.pcm' +// CHECK-NOT-USED-NOT: "-fmodule-output" +// CHECK-NOT-USED-NOT: "-fmodule-output=" + //--- AnotherModule.cppm export module AnotherModule; // CHECK: "-emit-module-interface" {{.*}}"-main-file-name" "Hello.cppm" {{.*}}"-o" "{{.*}}/Hello.pcm" "-x" "c++" "{{.*}}/Hello.cppm"