Question

On 2 separate machines in completely different environments (work, home) I’ve been unable to compile libCURL out of the box. Running nmake -f Makefile.vc mode=dll VC=10, I get an unresolved external symbol errors for _IdnToAscii and _IdnToUnicode. I believe the definitions are in Normaliz.lib, which is referenced in LFLAGS, but it either isn’t finding it or the version I have doesn’t have those functions. But I don’t see any option to download this file…anyone have a good solution short of commenting out the 2 lines that use these functions?

Answer 1

It looks like you don’t have the IDN API from Windows.
According to the Windows documentation:
http://msdn.microsoft.com/en-us/library/windows/desktop/dd318151%28v=vs.85%29.aspx

And to the libcurl building instructions:
https://github.com/bagder/curl/blob/master/winbuild/BUILD.WINDOWS.txt

IDN API is available from Vista and later and can be installed from:
http://www.microsoft.com/downloads/details.aspx?FamilyID=AD6158D7-DDBA-416A-9109-07607425A815

You can either build it on Vista or install the package from Microsoft or forgo IDN.
To build without IDN just pass ENABLE_IDN=no to the nmake.

NB: It’s important to delete the assorted build directories prior ro rerunning nmake with different parameters as some library references may be already in the generated object code.