undefined reference linking yaml-cpp program with mingw-w64 + cmake

Question

I'm using mingw-w64 (4.8.0) + cmake to build shared libraries for yaml-cpp (0.5.1). The project has a few build targets in the CMakeLists.txt that comes with it: the main library yaml-cpp and some test programs e.g. parse, which links the library.

The library target yaml-cpp itself built without error but it is followed by this error when parse is built:

Linking CXX executable parse.exe
CMakeFiles\parse.dir/objects.a(parse.cpp.obj):parse.cpp:(.text+0x1a3): undefined reference to `YAML::Load(std::istream&)'
CMakeFiles\parse.dir/objects.a(parse.cpp.obj):parse.cpp:(.text+0x1b2): undefined reference to `YAML::operator<<(std::ostream&, YAML::Node const&)'
c:/work/mingw64-4.8/bin/../lib/gcc/x86_64-w64-mingw32/4.8.0/../../../../x86_64-w64-mingw32/bin/ld.exe: CMakeFiles\parse.dir/objects.a(parse.cpp.obj): bad reloc address 0x0 in section `.data'
collect2.exe: error: ld returned 1 exit status
util\CMakeFiles\parse.dir\build.make:90: recipe for target 'util/parse.exe' failed
mingw32-make[3]: *** [util/parse.exe] Error 1
CMakeFiles\Makefile2:228: recipe for target 'util/CMakeFiles/parse.dir/all' failed
mingw32-make[2]: *** [util/CMakeFiles/parse.dir/all] Error 2
CMakeFiles\Makefile2:240: recipe for target 'util/CMakeFiles/parse.dir/rule' failed
mingw32-make[1]: *** [util/CMakeFiles/parse.dir/rule] Error 2
makefile:211: recipe for target 'parse' failed
mingw32-make: *** [parse] Error 2

I run into similar errors when I try to write small test programs using the library, and I don't know what is wrong. What might be the issue here?

Answer 1

Jesse Beder's comment points to the exact issue causing the error described in the question. A quick fix while this gets fixed in a follow-up release is to apply the patch (https://code.google.com/p/yaml-cpp/issues/detail?id=216#c4) to a clean copy of yaml-cpp 0.5.1. There is also a line that declares std::string node_data::empty_scalar in the source file src/node_data.cpp that should be commented out. After making these changes, the shared libraries and utilities build without error.