https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63346
--- Comment #3 from Peter Seiderer <ps.report at gmx dot net> --- Created attachment 36593 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=36593&action=edit Reduces test case from xserver_xorg-server-1.17.2/fb/fbpict.c Reduced (but not yet minimal) test case from the original xserver_xorg-server-1.17.2/fb/fbpict.c file. On x86_64: $ ./fbpict_x86 $ cat my.log fbGlyphs() pSrc = (nil) pDst = 0x602280 glyphs = 0x6021b0 glyphs = 0x6021b0 - 1 glyphs = 0x6021b8 - 2 glyphs = 0x602070 - 3 glyphs = 0x6021b8 - 1 glyphs = 0x6021c0 - 2 glyphs = 0x6020b0 - 3 glyphs = 0x6021c0 - 1 glyphs = 0x6021c8 - 2 glyphs = 0x6020f0 - 3 glyphs = 0x6021c8 - 1 glyphs = 0x6021d0 - 2 glyphs = 0x602130 - 3 glyphs = 0x6021d0 - 1 glyphs = 0x6021d8 - 2 glyphs = 0x602170 - 3 On Raspberry Pi (arm): $ ./fbpict_arm Segmentation fault $ cat my.log fbGlyphs() pSrc = (nil) pDst = 0x20c24 glyphs = 0x20ce4 glyphs = 0x20ce4 - 1 $ gdb ./fbpict_arm (gdb) run Starting program: /root/gcc_bug_63346/fbpict_arm Program received signal SIGSEGV, Segmentation fault. fbGlyphs (op=op@entry=0 '\000', pSrc=0x5, pSrc@entry=0x0, pDst=0x0, pDst@entry=0x20c24 <pictureRec.5609>, maskFormat=0x5, maskFormat@entry=0x0, xSrc=xSrc@entry=10, ySrc=ySrc@entry=10, nlist=-1, nlist@entry=5, list=list@entry=0x20c6c <glyphList.5618>, glyphs=0x5, glyphs@entry=0x20ce4 <glyph>) at fbpict.c:59 59 glyph = *glyphs++; (gdb) disassemble ... 0x00010658 <+272>: beq 0x10794 <fbGlyphs+588> 0x0001065c <+276>: ldrsh r3, [r4, #-12] 0x00010660 <+280>: add r10, r10, r3 0x00010664 <+284>: ldrsh r3, [r4, #-10] 0x00010668 <+288>: add r11, r11, r3 0x0001066c <+292>: ldrb r3, [r4, #-8] 0x00010670 <+296>: str r3, [sp, #52] ; 0x34 0x00010674 <+300>: ldr r3, [sp, #52] ; 0x34 0x00010678 <+304>: cmp r3, #0 0x0001067c <+308>: beq 0x10780 <fbGlyphs+568> 0x00010680 <+312>: add r3, sp, #6336 ; 0x18c0 0x00010684 <+316>: ldr r1, [r3] 0x00010688 <+320>: ldr r0, [pc, #684] ; 0x1093c <fbGlyphs+1012> 0x0001068c <+324>: bl 0x1098c <my_printf> => 0x00010690 <+328>: ldr r3, [r2] 0x00010694 <+332>: add r2, sp, #6336 ; 0x18c0 0x00010698 <+336>: ldr r7, [r3], #4 0x0001069c <+340>: ldr r0, [pc, #668] ; 0x10940 <fbGlyphs+1016> 0x000106a0 <+344>: str r3, [r2] 0x000106a4 <+348>: ldr r1, [r2] 0x000106a8 <+352>: bl 0x1098c <my_printf> 0x000106ac <+356>: mov r1, r7 0x000106b0 <+360>: ldr r0, [pc, #652] ; 0x10944 <fbGlyphs+1020> 0x000106b4 <+364>: bl 0x1098c <my_printf> 0x000106b8 <+368>: ldr r3, [pc, #632] ; 0x10938 <fbGlyphs+1008> 0x000106bc <+372>: mov r2, #0 0x000106c0 <+376>: mov r1, r7 0x000106c4 <+380>: ldr r0, [r3] 0x000106c8 <+384>: bl 0x10970 <pixman_glyph_cache_lookup> 0x000106cc <+388>: subs r9, r0, #0 0x000106d0 <+392>: bne 0x10748 <fbGlyphs+512> 0x000106d4 <+396>: ldr r1, [sp, #84] ; 0x54 0x000106d8 <+400>: mov r0, r7 0x000106dc <+404>: bl 0x10978 <GetGlyphPicture>
