[Bug c++/21222] A function with a particular number of arguments corrupts a value calculated on the stack when stepping through the function

[kungfujesus06 at gmail dot com]

https://sourceware.org/bugzilla/show_bug.cgi?id=21222

--- Comment #4 from Adam Stylinski <kungfujesus06 at gmail dot com> ---
Also I did search the registers as well, and it's not in the register it should
be in (xmm0) or any of the other vector registers either.  I've compiled with
-fno-omit-frame-pointer and I still see the issue.  The number of arguments to
the function seems to have an affect on whether or not the issue happens.  That
was the bare minimum number of arguments before the issue showed up. 

(gdb) disass
Dump of assembler code for function testFunc(float*, unsigned long, float*,
float*, float*, float, int, float, float**, float**, float**, float*, float*):
   0x0000000000400526 <+0>:     push   %rbp
   0x0000000000400527 <+1>:     mov    %rsp,%rbp
   0x000000000040052a <+4>:     sub    $0x50,%rsp
   0x000000000040052e <+8>:     mov    %rdi,-0x18(%rbp)
   0x0000000000400532 <+12>:    mov    %rsi,-0x20(%rbp)
   0x0000000000400536 <+16>:    mov    %rdx,-0x28(%rbp)
   0x000000000040053a <+20>:    mov    %rcx,-0x30(%rbp)
   0x000000000040053e <+24>:    mov    %r8,-0x38(%rbp)
   0x0000000000400542 <+28>:    vmovss %xmm0,-0x3c(%rbp)
   0x0000000000400547 <+33>:    mov    %r9d,-0x40(%rbp)
   0x000000000040054b <+37>:    vmovss %xmm1,-0x44(%rbp)
   0x0000000000400550 <+42>:    vmovss 0x11c(%rip),%xmm0        # 0x400674
   0x0000000000400558 <+50>:    vdivss -0x44(%rbp),%xmm0,%xmm0
   0x000000000040055d <+55>:    vmovss %xmm0,-0x4(%rbp)
=> 0x0000000000400562 <+60>:    vcvtss2sd -0x4(%rbp),%xmm2,%xmm2
   0x0000000000400567 <+65>:    vmovq  %xmm2,%rax
   0x000000000040056c <+70>:    vmovq  %rax,%xmm0
   0x0000000000400571 <+75>:    mov    $0x400664,%edi
   0x0000000000400576 <+80>:    mov    $0x1,%eax
   0x000000000040057b <+85>:    callq  0x400420 <printf@plt>
   0x0000000000400580 <+90>:    nop
   0x0000000000400581 <+91>:    leaveq 
   0x0000000000400582 <+92>:    retq   
End of assembler dump.

Here are the register contents:
http://pastebin.com/Mq4QVu24

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