[Numpy-discussion] Byte aligned arrays

Sturla Molden sturla at molden.no
Thu Dec 20 15:45:07 EST 2012

On 20.12.2012 21:24, Henry Gomersall wrote:

> I didn't know that. It's a real pain having so many libc libs knocking
> around. I have little experience of Windows, as you may have guessed!

Originally there was only one system-wide CRT on Windows (msvcrt.dll), 
which is why MinGW linkes with that by default. But starting with the 
release of VS2003, Microsoft decided to reserve msvcrt.dll for system 
resources and create a libc "DLL Hell" for user apps. Visual Studio 2003 
came with static and dynamic versions of the CRT library, as well as 
single- and multithreaded ones... Then everyone building apps that used 
DLLs or COM objects just had to make sure that nothing conflicted. And 
for every later version of Visual Studio they have released further more 
CRT versions, adding to the confusion.

Currently: The official Python 2.7 binaries are built with Visual Studio 
2008 and linked with msvcr90.dll.

MinGW has import libraries for the other CRTs Microsoft has released, so 
just add -lmsvcr90 to your final linkage.

Python's distutils will control the build process for extensions 
automatically. Adding -lmsvcr90 is one of the things that distutils will 


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