[openssl-users] Unhandled exception at 0x005904dc (libeay32.dll) (Windows x86)

[Jakob Bohm]

On 22/08/2016 20:09, Scott Ware wrote:
> We use libeay32.dll and ssleay32.dll from 
> https://slproweb.com/products/Win32OpenSSL.htmlin our applications and 
> we recently moved from version 1.0.2a to 1.0.2g and now on a few 
> machines running a AMD Geode processor we are getting "Unhandled 
> exception at 0x005904dc (libeay32.dll) in Test.exe: 0xC000001D: 
> Illegal Instruction". We ended up building OpennSSL so we could debug 
> into it and found it is failing on "movsd xmm0,mmword" (see below) 
> which the AMD Geode does not seem to support. I have tried "SET 
> OPENSSL_ia32cap=~0x1000000", "SET OPENSSL_ia32cap=~0x2000000", and 
> "SET OPENSSL_ia32cap=~0x7000000"; and nothing seems to change. I may 
> not be using OPENSSL_ia32cap correctly. This happens when calling 
> SSL_CTX_new which then calls RAND_add.
>
> Any ideas on the best thing to do? We don't want to have to manage 
> different compiled versions of libeay32.dll and ssleay32.dll if we can 
> help it.
>
Your disassembly looks like the C compiler was invoked with
options that caused regular C floating point code (in this
case, the passing of 45.0 as an argument to RAND_add()) to
be compiled into MMX/SSE instructions instead of backwards
compatible 80x87 floating point instructions or (for simple
cases like this) regular integer unit data movement
instructions (such as two pushes of 32 bit constants that
contain the halves of the 64 bit double constant, which
would have been more efficient on every x86 CPU).

Did the build scripts or other source code contain any
differences from the official source code that can be
downloaded from openssl.org?

How did you invoke the build scripts (command sequence,
special build environment, special environment variables
etc.)?

Which compiler and compiler version/edition did you use?

It would be interesting to know if one of the common Windows
compilers does this unconditionally, making it unsuitable
for use in programs that need to be backwards compatible.


Enjoy

Jakob
-- 
Jakob Bohm, CIO, Partner, WiseMo A/S.  https://www.wisemo.com
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