https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111601
--- Comment #15 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Looking at the assembly difference, I see just a few functions: --- cp/call.s2 2023-11-27 13:40:15.088908624 +0000 +++ cp/call.s1 2023-11-27 13:35:56.912298399 +0000 @@ -364,13 +364,12 @@ _ZL13splice_viableP11z_candidatebPb: std 9,0(10) mr 10,9 li 11,0 - addi 10,10,96 li 7,1 addi 6,6,1 addi 12,12,1 ld 9,96(9) std 9,0(8) - std 11,0(10) + std 11,96(10) stb 7,0(5) ori 2,2,0 ld 9,0(8) @@ -449,10 +448,9 @@ _ZL13splice_viableP11z_candidatebPb: .cfi_restore 25 std 9,0(10) mr 10,9 - addi 10,10,96 li 26,0 - ld 7,.LANCHOR0+136@toc@l(11) li 28,0 + ld 7,.LANCHOR0+136@toc@l(11) addi 6,6,1 addi 12,12,1 addi 7,7,1 @@ -461,8 +459,9 @@ _ZL13splice_viableP11z_candidatebPb: li 11,0 li 7,1 std 9,0(8) - std 11,0(10) + std 11,96(10) stb 7,0(5) + ori 2,2,0 ld 9,0(8) cmpdi 0,9,0 bne 0,.L104 @@ -21377,24 +21376,22 @@ _ZN2wi5lts_pI16generic_wide_intINS_13ext nop addis 10,2,.LANCHOR0+5848@toc@ha mr 5,30 - addi 29,1,64 ld 9,.LANCHOR0+5848@toc@l(10) - std 3,0(29) + std 3,64(1) addi 3,1,48 - std 4,8(29) + std 4,72(1) lis 4,0x2 addi 9,9,1 std 9,.LANCHOR0+5848@toc@l(10) bl _ZN2wi10int_traitsI16generic_wide_intINS_13extended_treeILi131072EEEEE9decomposeEPljRKS4_ nop - addi 9,1,32 lwz 30,72(1) ld 29,64(1) rldicl 7,4,0,32 + std 3,32(1) + std 4,40(1) mr 6,3 cmplwi 0,7,1 - std 3,0(9) - std 4,8(9) beq 0,.L2422 addis 10,2,.LANCHOR0+5912@toc@ha rldicl 4,30,0,32 @@ -51700,10 +51697,9 @@ _ZL8op_errorRK13op_location_t9tree_codeS addis 7,2,.LC1285@toc@ha ld 7,.LC1285@toc@l(7) lbzx 10,10,5 - addi 10,10,58 sldi 10,10,5 add 10,7,10 - ld 29,8(10) + ld 29,1864(10) .L6276: cmpdi 0,30,0 beq 0,.L6338 @@ -172014,7 +172010,7 @@ __gcov7._Z15good_conversionP9tree_nodeS0 .long 1110716448 .zero 4 .quad 0 - .long 285183267 + .long 284929938 .long 1725772321 .quad .LC2647 .quad __gcov_merge_add While most of the changes look reasonable (but I haven't so far verified if the removed additions turned into memory immediates set registers which aren't used in other places), the addition of ori 2,2,0 instruction seems kind of unexpected.