Invalid symbols name when compiling libraries with VS2012

Question

I compiled libraries with Visual Studio 2012 (portaudio and opus), and when I try to use them in a QT project tells me he didn't find the symbols.

However, when I remove the .lib file, I encounter another error saying me that the lib doesn't exist, so the lib is well found.

When doing a dumpbin.exe /SYMBOLS portaudio.lib I have the missing symbols, but with a _ in front of it!

I don't understand, first time manipulating libraries on Windows and it drives me crazy!

In my .pro I have:

win32:LIBS += -L$$PWD
win32:LIBS += -lopus
win32:LIBS += -lporaudio

Answer 1

The problem is that you are mixing 32 and 64 bit.

The symbol names with an underscore prefix happen to be in 32 bit libraries due to the __cdecl calling convention. This is not the case with 64 bit libraries where this theory is obsolete.

If you wish to build a 32 bit project, build 32 bit portaudio and opus, and configure your project for 32 bit accordingly.

If you wish to build a 64 bit project, use 64 bit library dependencies, i.e. build portaudio and opus so. Then make sure that you also have 64 bit project configuration for your own project.