[openssl-dev] [openssl.org #4509] ECC key generation under valgrind reports: impossible has happened

[Andy Polyakov via RT]

>>> Valgrind does not necessarily support all instructions, if there’s
>>> any optimized assembly, you might run into problems.
>>> Are you able to compile a non-assembly version of the OpenSSL
>>> library?
>>> Are you able to update to a newer Valgrind?
>> Or at least tell valgrind version, because I can't reproduce the
>> problem
>> with 3.10.1. At any event you can also see if it's problem with
>> unsupported instructions, unsupported by [your version of] valgrind
>> that
>> is, by manipulating OPENSSL_ia32cap environment variable. You can
>> disable AVX2 code paths by setting it to :~0x20 or simply :0 if it
>> runs into more "too-new-to-be-possible" instructions.
> 
> I tried with valgrind-3.11.0.

Tough break... One can actually wonder if valgrind tampers with
processor capability vector... And it totally does! I.e. even though my
processor is AVX2-capable, when executed under my valgrind openssl
doesn't see it as AVX2-capable. I suppose your valgrind passed AVX2
flag, but failed to recognize all the instructions it should have...



-- 
Ticket here: http://rt.openssl.org/Ticket/Display.html?id=4509
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