• Mark Rutland's avatar
    Kbuild: use -Wdeclaration-after-statement · 4d94f910
    Mark Rutland authored
    The kernel is moving from using `-std=gnu89` to `-std=gnu11`, permitting
    the use of additional C11 features such as for-loop initial declarations.
    
    One contentious aspect of C99 is that it permits mixed declarations and
    code, and for now at least, it seems preferable to enforce that
    declarations must come first.
    
    These warnings were already enabled in the kernel itself, but not
    for KBUILD_USERCFLAGS or the compat VDSO on arch/arm64, which uses
    a separate set of CFLAGS.
    
    This patch fixes an existing violation in modpost.c, which is not
    reported because of the missing flag in KBUILD_USERCFLAGS:
    
    | scripts/mod/modpost.c: In function ‘match’:
    | scripts/mod/modpost.c:837:3: warning: ISO C90 forbids mixed declarations and code [-Wdeclaration-after-statement]
    |   837 |   const char *endp = p + strlen(p) - 1;
    |       |   ^~~~~
    Signed-off-by: default avatarMark Rutland <mark.rutland@arm.com>
    [arnd: don't add a duplicate flag to the default set, update changelog]
    Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
    Reviewed-by: default avatarNathan Chancellor <nathan@kernel.org>
    Reviewed-by: default avatarNick Desaulniers <ndesaulniers@google.com>
    Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM/Clang v13.0.0 (x86-64)
    Signed-off-by: default avatarMasahiro Yamada <masahiroy@kernel.org>
    4d94f910
Makefile 6.55 KB