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    SubjectSegfault on the i386 enter instruction
    The code attached below segfaults on the enter instruction. It works
    when a stack frame is created by the three commented out
    instructions and also when the first operand of the enter instruction
    is small (less than about 6500 on my system).

    AFAIK, the only difference between creating a stack frame with the
    enter instruction or push/mov/sub is that enter checks if the new
    value of esp is inside the stack segment limit.

    I tested it on a vanilla kernel 2.4.26 on Intel Celeron and also on
    probably non-vanilla 2.6.16.13 running on 3 dual core AMD Opteron,
    quite busy, server. It is working in 32-bit mode. Interestingly, on
    the second machine sometimes the program worked correctly.

    I am not subscribed to the list. Please cc replies to me.


    .file "a.c"
    .version "01.01"
    gcc2_compiled.:
    .section .rodata
    .LC0:
    .string "asdf\n"
    .text
    .align 4
    .globl main
    .type main,@function
    main:
    enter $10008, $0
    # pushl %ebp
    # movl %esp,%ebp
    # subl $10008,%esp
    addl $-12,%esp
    pushl $.LC0
    call printf
    addl $16,%esp
    .L2:
    leave
    ret
    .Lfe1:
    .size main,.Lfe1-main
    .ident "GCC: (GNU) 2.95.4 20011002 (Debian prerelease)"

    --
    Tomek Malesinski
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