$ cmake .
-- The C compiler identification is GNU
-- Checking whether C compiler has -isysroot
-- Checking whether C compiler has -isysroot - yes
-- Check for working C compiler: /usr/bin/gcc
-- Check for working C compiler: /usr/bin/gcc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Found BISON: /usr/bin/bison
-- Found FLEX: /usr/bin/flex
-- Looking for _assert_true in cmockery
-- Looking for _assert_true in cmockery - found
-- Configuring done
-- Generating done
-- Build files have been written to: /Users/sebastian/projects/development/pkgparse
$ make
[ 20%] [BISON][pkgbuild_parser] Building parser with bison 2.3
Scanning dependencies of target pkgparse
[ 40%] Building C object CMakeFiles/pkgparse.dir/pkgbuild.o
[ 60%] Building C object CMakeFiles/pkgparse.dir/symbol.o
[ 80%] Building C object CMakeFiles/pkgparse.dir/utility.o
[100%] Building C object CMakeFiles/pkgparse.dir/pkgbuild_parse.o
Linking C shared library libpkgparse.dylib
Undefined symbols:
  "_yyerror", referenced from:
      _yyparse in pkgbuild_parse.o
      _yyparse in pkgbuild_parse.o
  "_yylex", referenced from:
      _yyparse in pkgbuild_parse.o
  "_yyin", referenced from:
      _yyin$non_lazy_ptr in pkgbuild_parse.o
ld: symbol(s) not found
collect2: ld returned 1 exit status
make[2]: *** [libpkgparse.dylib] Error 1
make[1]: *** [CMakeFiles/pkgparse.dir/all] Error 2
make: *** [all] Error 2
$ cat CMakeLists.txt
project(pkgparse C)

find_package(BISON)
find_package(FLEX)

BISON_TARGET(pkgbuild_parser pkgbuild_parse.y ${CMAKE_CURRENT_BINARY_DIR}/pkgbuild_parse.c)
FLEX_TARGET(pkgbuild_scanner pkgbuild_scanner.l ${CMAKE_CURRENT_BIANRY_DIR}/pkgbuild_scanner.c)
ADD_FLEX_BISON_DEPENDENCY(pkgbuild_scanner pkgbuild_parser)

set(pkgparse_SRCS
  pkgbuild.c
  symbol.c
  utility.c
  ${BISON_pkgbuild_parser_OUTPUTS}
  ${FLEX_pkgbuild_parser_OUTPUTS}
)

#include_directories(${CMAKE_CURRENT_BINARY_DIR})

add_library(pkgparse SHARED ${pkgparse_SRCS})

include(CheckLibraryExists)
check_library_exists(cmockery _assert_true "" HAVE_CMOCKERY)

# Unit tests
if(HAVE_CMOCKERY)
  add_custom_target(test COMMAND ${CMAKE_TEST_COMMAND})
  add_executable(test_runner EXCLUDE_FROM_ALL test_runner.c pkgbuild_test.c symbol_test.c utility_test.c)
  add_test(test_runner test_runner)
  add_dependencies(test test_runner)
  find_library(cmockery_LIBRARY NAMES cmockery)
  set(cmockery_PROCESS_LIBS cmockery_LIBRARY cmockery_LIBRARIES)
  target_link_libraries(test_runner pkgparse cmockery)
endif(HAVE_CMOCKERY)