From d9fa9b7c3306008ee97140a3aafc56999d8cd2cd Mon Sep 17 00:00:00 2001 From: Tsukasa OI Date: Mon, 12 Sep 2022 08:04:40 +0000 Subject: [PATCH] include: Add macro to ignore -Wunused-but-set-variable "-Wunused-but-set-variable" warning option can be helpful to track variables that are written but not read thereafter. But it can be harmful if some of the code is auto-generated and we have no ways to deal with it. The particular example is Bison-generated code. The new DIAGNOSTIC_IGNORE_UNUSED_BUT_SET_VARIABLE macro can be helpful on such cases. A typical use of this macro is to place this macro before the end of user prologues on Bison (.y) files. include/ChangeLog: * diagnostics.h (DIAGNOSTIC_IGNORE_UNUSED_BUT_SET_VARIABLE): New. --- include/diagnostics.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/include/diagnostics.h b/include/diagnostics.h index dbe6288d3d6..4161dff6abc 100644 --- a/include/diagnostics.h +++ b/include/diagnostics.h @@ -68,6 +68,11 @@ DIAGNOSTIC_IGNORE ("-Wuser-defined-warnings") # endif +# if __has_warning ("-Wunused-but-set-variable") +# define DIAGNOSTIC_IGNORE_UNUSED_BUT_SET_VARIABLE \ + DIAGNOSTIC_IGNORE ("-Wunused-but-set-variable") +# endif + # define DIAGNOSTIC_ERROR_SWITCH \ DIAGNOSTIC_ERROR ("-Wswitch") @@ -89,6 +94,11 @@ # define DIAGNOSTIC_IGNORE_FORMAT_NONLITERAL \ DIAGNOSTIC_IGNORE ("-Wformat-nonliteral") +# if __GNUC__ >= 5 +# define DIAGNOSTIC_IGNORE_UNUSED_BUT_SET_VARIABLE \ + DIAGNOSTIC_IGNORE ("-Wunused-but-set-variable") +# endif + /* GCC 4.8's "diagnostic push/pop" seems broken when using this, -Wswitch remains enabled at the error level even after a pop. Therefore, don't use it for GCC < 5. */ @@ -130,6 +140,10 @@ # define DIAGNOSTIC_IGNORE_USER_DEFINED_WARNINGS #endif +#ifndef DIAGNOSTIC_IGNORE_UNUSED_BUT_SET_VARIABLE +# define DIAGNOSTIC_IGNORE_UNUSED_BUT_SET_VARIABLE +#endif + #ifndef DIAGNOSTIC_ERROR_SWITCH # define DIAGNOSTIC_ERROR_SWITCH #endif -- 2.30.2