From a9f4703d9341507b5a25924de1410df5bf260adc Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Thu, 28 Mar 2019 15:24:35 -0700 Subject: gcc PR 89877: miscompilation due to missing cc clobber in longlong.h macros simple test such as below was failing. | void main(int argc, char *argv[]) | { | size_t total_time = 115424; // expected 115.424 | double secs = (double)total_time/(double)1000; | printf("%s %d %lf\n", "secs", total_time, secs); // prints 113.504 | printf("%d\n", (size_t)secs); | } The printf eventually called into glibc stdlib/divrem.c:__mpn_divrem() which uses the __arc__ specific inline asm macros from longlong.h which were causing miscompilation. include/ 2019-03-28 Vineet Gupta PR 89877 * longlong.h [__arc__] (add_ssaaaa): Add cc clobber (sub_ddmmss): Likewise. Signed-off-by: Vineet Gupta --- stdlib/longlong.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/stdlib/longlong.h b/stdlib/longlong.h index ee4aac1bb5..638b7894d4 100644 --- a/stdlib/longlong.h +++ b/stdlib/longlong.h @@ -199,7 +199,8 @@ extern UDItype __udiv_qrnnd (UDItype *, UDItype, UDItype, UDItype); : "%r" ((USItype) (ah)), \ "rICal" ((USItype) (bh)), \ "%r" ((USItype) (al)), \ - "rICal" ((USItype) (bl))) + "rICal" ((USItype) (bl)) \ + : "cc") #define sub_ddmmss(sh, sl, ah, al, bh, bl) \ __asm__ ("sub.f %1, %4, %5\n\tsbc %0, %2, %3" \ : "=r" ((USItype) (sh)), \ @@ -207,7 +208,8 @@ extern UDItype __udiv_qrnnd (UDItype *, UDItype, UDItype, UDItype); : "r" ((USItype) (ah)), \ "rICal" ((USItype) (bh)), \ "r" ((USItype) (al)), \ - "rICal" ((USItype) (bl))) + "rICal" ((USItype) (bl)) \ + : "cc") #define __umulsidi3(u,v) ((UDItype)(USItype)u*(USItype)v) #ifdef __ARC_NORM__ -- cgit v1.2.3-65-gdbad