From: Arnd Bergmann Date: Thu, 7 Aug 2025 20:53:28 +0000 (+0200) Subject: x86/math-emu: Fix div_Xsig() prototype X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=780813d7018067f2796f023b56b51385970be460;p=thirdparty%2Fkernel%2Flinux.git x86/math-emu: Fix div_Xsig() prototype The third argument of div_Xsig() is the output of the division, but is marked 'const', which means the compiler is not expecting it to be updated and may generate bad code around the call. clang-21 now warns about the pattern since an uninitialized variable is passed into two 'const' arguments by reference: arch/x86/math-emu/poly_atan.c:93:28: error: variable 'argSignif' is uninitialized \ when passed as a const pointer argument here [-Werror,-Wuninitialized-const-pointer] 93 | div_Xsig(&Numer, &Denom, &argSignif); | ^~~~~~~~~ arch/x86/math-emu/poly_l2.c:195:29: error: variable 'argSignif' is uninitialized \ when passed as a const pointer argument here [-Werror,-Wuninitialized-const-pointer] 195 | div_Xsig(&Numer, &Denom, &argSignif); | ^~~~~~~~~ The implementation is in assembly, so the problem has gone unnoticed since the code was added in the linux-1.1 days. Remove the 'const' marker here. Fixes: e19a1bdb835c ("Import 1.1.38") Signed-off-by: Arnd Bergmann Signed-off-by: Borislav Petkov (AMD) Link: https://patch.msgid.link/20250807205334.123231-1-arnd@kernel.org --- diff --git a/arch/x86/math-emu/poly.h b/arch/x86/math-emu/poly.h index fc1c887ca0731..654bfe4e29a0c 100644 --- a/arch/x86/math-emu/poly.h +++ b/arch/x86/math-emu/poly.h @@ -39,7 +39,7 @@ asmlinkage void mul_Xsig_Xsig(Xsig *dest, const Xsig *mult); asmlinkage void shr_Xsig(Xsig *, const int n); asmlinkage int round_Xsig(Xsig *); asmlinkage int norm_Xsig(Xsig *); -asmlinkage void div_Xsig(Xsig *x1, const Xsig *x2, const Xsig *dest); +asmlinkage void div_Xsig(Xsig *x1, const Xsig *x2, Xsig *dest); /* Macro to extract the most significant 32 bits from a long long */ #define LL_MSW(x) (((unsigned long *)&x)[1])