Openssl 1.0.2t build failed using Visual Studio

Matt Caswell matt at
Thu Sep 12 16:28:35 UTC 2019

On 12/09/2019 10:29, Fabrice Manfroi wrote:
> Hello,
> Trying to build the last 1.0.2t on Windows with Visual Studio 2010, I
> get the following build error:
> ===
> LIBEAY32.def : error LNK2001: unresolved external symbol OPENSSL_rdtsc
> ===
> If I remove the OPENSSL_rdtsc entry from the util/libeay.num file it
> works without any probleme.
> Is it a error? Or do I miss something?

I don't get this with VS2013 (the oldest version I have) so it may be a Visual
Studio version specific problem.

OPENSSL_rdtsc is only relevant on some platforms, and isn't present on others
which is why this problem occurs. Perhaps later Visual Studio versions are more
tolerant of this? Removing the entry from util/libeay.num is fine as a
workaround for now, and won't cause any adverse impacts.


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