| Message ID | 20170719125310.2487451-4-arnd@arndb.de |
|---|---|
| State | Accepted |
| Commit | 5623452a0eaec1d44cc9f0770444a48847c9953f |
| Headers | show |
| Series | x86: randconfig warning fixes | expand |
diff --git a/arch/x86/math-emu/fpu_emu.h b/arch/x86/math-emu/fpu_emu.h index afbc4d805d66..c9c320dccca1 100644 --- a/arch/x86/math-emu/fpu_emu.h +++ b/arch/x86/math-emu/fpu_emu.h @@ -157,7 +157,7 @@ extern u_char const data_sizes_16[32]; #define signbyte(a) (((u_char *)(a))[9]) #define getsign(a) (signbyte(a) & 0x80) -#define setsign(a,b) { if (b) signbyte(a) |= 0x80; else signbyte(a) &= 0x7f; } +#define setsign(a,b) { if ((b) != 0) signbyte(a) |= 0x80; else signbyte(a) &= 0x7f; } #define copysign(a,b) { if (getsign(a)) signbyte(b) |= 0x80; \ else signbyte(b) &= 0x7f; } #define changesign(a) { signbyte(a) ^= 0x80; }
gcc-7.1.1 produces this warning: arch/x86/math-emu/reg_add_sub.c: In function 'FPU_add': arch/x86/math-emu/reg_add_sub.c:80:48: error: ?: using integer constants in boolean context [-Werror=int-in-bool-context] This appears to be a bug in gcc-7.1.1, and I have reported it as PR81484. The compiler suggests that code written as if (a & b ? c : d) is usually incorrect and should have been if (a & (b ? c : d)) However, in this case, we correctly write if ((a & b) ? c : d) and should not get a warning for it. This adds a dirty workaround for the problem, adding a comparison with zero inside of the macro. The warning is currently disabled in the kernel, so we may decide not to apply the patch, and instead wait for future gcc releases to fix the problem. On the other hand, it seems to be the only instance of this particular problem. Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81484 Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- Originally sent on July 14, this is the same patch again with an rewritten changelog. --- arch/x86/math-emu/fpu_emu.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.9.0