From: Anders Roxell Date: Fri, 11 Dec 2020 10:24:37 +0000 (+0100) Subject: mips: lib: uncached: fix non-standard usage of variable 'sp' X-Git-Tag: accepted/tizen/unified/20230118.172025~8266^2~7 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=5b058973d3205578aa6c9a71392e072a11ca44ef;p=platform%2Fkernel%2Flinux-rpi.git mips: lib: uncached: fix non-standard usage of variable 'sp' When building mips tinyconfig with clang the following warning show up: arch/mips/lib/uncached.c:45:6: warning: variable 'sp' is uninitialized when used here [-Wuninitialized] if (sp >= (long)CKSEG0 && sp < (long)CKSEG2) ^~ arch/mips/lib/uncached.c:40:18: note: initialize the variable 'sp' to silence this warning register long sp __asm__("$sp"); ^ = 0 1 warning generated. Rework to make an explicit inline move, instead of the non-standard use of specifying registers for local variables. This is what's written from the gcc-10 manual [1] about specifying registers for local variables: "6.47.5.2 Specifying Registers for Local Variables ................................................. [...] "The only supported use for this feature is to specify registers for input and output operands when calling Extended 'asm' (*note Extended Asm::). [...]". [1] https://docs.w3cub.com/gcc~10/local-register-variables Signed-off-by: Anders Roxell Reported-by: Nathan Chancellor Reported-by: Naresh Kamboju Reviewed-by: Nick Desaulniers Signed-off-by: Thomas Bogendoerfer --- diff --git a/arch/mips/lib/uncached.c b/arch/mips/lib/uncached.c index 09d5dee..f80a67c 100644 --- a/arch/mips/lib/uncached.c +++ b/arch/mips/lib/uncached.c @@ -37,10 +37,12 @@ */ unsigned long run_uncached(void *func) { - register long sp __asm__("$sp"); register long ret __asm__("$2"); long lfunc = (long)func, ufunc; long usp; + long sp; + + __asm__("move %0, $sp" : "=r" (sp)); if (sp >= (long)CKSEG0 && sp < (long)CKSEG2) usp = CKSEG1ADDR(sp);