Build Tricks

This page collects some known build errors and trick how to fix them

FreeBSD

undefined reference to `backtrace_symbols'

If compilation fails because of the following errors

undefined reference to `backtrace_symbols'
undefined reference to `backtrace'

then you need to link to execinfo:

if [[ "${target}" == *-freebsd* ]]; then
    export LDFLAGS="-lexecinfo"
fi
./configure --prefix=${prefix} --build=${MACHTYPE} --host=${target}
make -j ${nprocs}
make install

Windows

Libtool refuses to build shared library because of undefined symbol

When building for Windows, sometimes libtool refuses to build the shared library. For example you can get

libtool: warning: undefined symbols not allowed in i686-w64-mingw32 shared libraries; building static only

or

libtool:   error: can't build i686-w64-mingw32 shared library unless -no-undefined is specified

In these cases you have to pass the -no-undefined option to the linker, as explicitly suggested by the second message.

Doing this properly is a bit tricky: I couldn't make CFLAGS=-Wl,-no-undefined work, instead setting LDFLAGS=-no-undefined before ./configure make this fail (because it will run a command like cc -no-undefined conftest.c). What I use to do is to pass LDFLAGS=-no-undefined only to make:

FLAGS=()
if [[ "${target}" == *-mingw* ]]; then
    FLAGS+=(LDFLAGS="-no-undefined")
fi
./configure --prefix=${prefix} --build=${MACHTYPE} --host=${target}
make -j ${nprocs} "${FLAGS[@]}"
make install