toolchain/59461: m68k gcc miscompiles pkgsrc x11/rxvt

[martin%NetBSD.org@localhost]

>Number:         59461
>Category:       toolchain
>Synopsis:       m68k gcc miscompiles pkgsrc x11/rxvt
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    toolchain-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Jun 09 17:25:00 +0000 2025
>Originator:     MartinHusemann
>Release:        NetBSD 10.99.14
>Organization:
The NetBSD Foundation, Inc.
>Environment:
System: NetBSD amiga.aprisoft.de 10.99.14 NetBSD 10.99.14 (GENERIC) #6: Sun Jun 8 08:11:46 CEST 2025 martin%seven-days-to-the-wolves.aprisoft.de@localhost:/work/src/sys/arch/amiga/compile/GENERIC amiga
Architecture: m68k
Machine: amiga
>Description:

Trying to run x11/rxvt from pkgsrc fails immediately with a stack check
failure:

Reading symbols from /usr/pkg/bin/rxvt...
[New process 28472]
Core was generated by `rxvt'.
Program terminated with signal SIGABRT, Aborted.
#0  0x0e2da778 in _lwp_kill () from /usr/lib/libc.so.12
(gdb) bt
#0  0x0e2da778 in _lwp_kill () from /usr/lib/libc.so.12
#1  0x0e2da726 in raise (s=6) at /work/src/lib/libc/gen/raise.c:48
#2  0x0e2bd550 in __fail (msg=0xe2efcff "stack overflow detected; terminated")
    at /work/src/lib/libc/misc/stack_protector.c:104
#3  0x0e2bd572 in __stack_chk_fail ()
    at /work/src/lib/libc/misc/stack_protector.c:111
#4  0x0000d806 in rxvt_tt_winsize ()
#5  0x00015f24 in rxvt_scr_reset ()
#6  0x0000f474 in rxvt_init ()
#7  0x0001d076 in main ()
(gdb) up 4
#4  0x0000d806 in rxvt_tt_winsize ()
(gdb) disas
Dump of assembler code for function rxvt_tt_winsize:
   0x0000d794 <+0>:     linkw %fp,#-12
   0x0000d798 <+4>:     movel %a5,%sp@-
   0x0000d79a <+6>:     movel %a2,%sp@-
   0x0000d79c <+8>:     lea %pc@(0x27690),%a5
   0x0000d7a4 <+16>:    movel %fp@(8),%d0
   0x0000d7a8 <+20>:    moveal %fp@(12),%a0
   0x0000d7ac <+24>:    movel %fp@(16),%d1
   0x0000d7b0 <+28>:    moveaw %fp@(-4),%a1
   0x0000d7b4 <+32>:    moveaw %fp@(-2),%a1
   0x0000d7b8 <+36>:    moveal %a5@(468),%a2
   0x0000d7c0 <+44>:    moveal %a2@,%a1
   0x0000d7c2 <+46>:    tstl %d0
   0x0000d7c4 <+48>:    blts 0xd7ec <rxvt_tt_winsize+88>
   0x0000d7c6 <+50>:    movew %a0,%fp@(-10)
   0x0000d7ca <+54>:    movew %d1,%fp@(-12)
   0x0000d7ce <+58>:    clrw %fp@(-6)
   0x0000d7d2 <+62>:    clrw %fp@(-8)
   0x0000d7d6 <+66>:    pea %fp@(-12)
   0x0000d7da <+70>:    movel #-2146929561,%sp@-
   0x0000d7e0 <+76>:    movel %d0,%sp@-
   0x0000d7e2 <+78>:    bsrl 0x87a8 <ioctl@plt>
   0x0000d7e8 <+84>:    lea %sp@(12),%sp
   0x0000d7ec <+88>:    movew %fp@(-4),%d0
   0x0000d7f0 <+92>:    swap %d0
   0x0000d7f2 <+94>:    clrw %d0
   0x0000d7f4 <+96>:    movew %fp@(-2),%d1
   0x0000d7f8 <+100>:   orw %d1,%d0
   0x0000d7fa <+102>:   movel %a2@,%d1
   0x0000d7fc <+104>:   cmpl %d1,%d0
   0x0000d7fe <+106>:   beqs 0xd806 <rxvt_tt_winsize+114>
   0x0000d800 <+108>:   bsrl 0x7f88 <__stack_chk_fail@plt>
=> 0x0000d806 <+114>:   moveal %fp@(-20),%a2
   0x0000d80a <+118>:   moveal %fp@(-16),%a5
   0x0000d80e <+122>:   unlk %fp
   0x0000d810 <+124>:   rts

rxvt_tt_winsize is a quite simple function with the speciallity of
receiving 16byte arguments.

void
rxvt_tt_winsize(int fd, unsigned short col, unsigned short row)
{
    struct winsize  ws;
 
    if (fd < 0)
        return;
    ws.ws_col = col;
    ws.ws_row = row;
    ws.ws_xpixel = ws.ws_ypixel = 0;
    ioctl(fd, TIOCSWINSZ, &ws);
}


>How-To-Repeat:

run rxvt on m68k -current.

>Fix:
n/a