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Re: Static Libcurl crashes on MSVC13

From: Ray Satiro via curl-library <>
Date: Fri, 26 Feb 2016 17:35:45 -0500

On 2/26/2016 4:45 AM, Jules van der Toorn wrote:
> Thanks for your answer on my previous question about how to only
> receive the subject of the most recent mail, it worked perfectly.
> I build libCurl to a static library, but now i want to convert it to a
> static library.
> I followed the guide of mtlynch on this page:
> When i build the simple code he gave in his guide, it works great.
> However if i use my (working with the dynamic library) mail receive
> program, MSVC gives an error: first it says "program.exe has triggered
> a breakpoint", and if i click continue it says: "Debug Assertion
> Failed!" "Expression: _CrtIsValidHeapPointer(pUserData)"
> I already tried rebuilding with MACHINE=x64 (My pc is x64, but MSVC is
> x86).

I think Gisle is right, what you are seeing is likely because you are
mixing debug and release static libraries. The directions you cite are
for the release configuration not for the debug configuration. If you
use those directions on a debug configuration then you will see a heap
validation error. For more information please refer to

Also could you please not top post it's making the conversation hard to

List admin:
Received on 2016-02-26