cmake: fix semicolons in CFLAGS of custom modules

Both `openssl.cmake` and `pcscd.cmake` use FindPkgConfig to retrieve the
required CFLAGS and LDFLAGS. However FindPkgConfig returns lists [1],
which are stored as semicolon-separated strings in CMake.  This breaks
the build when there's more than one flag in any of those variables.

Fixes Yubico#474

CMakeLists.txt

@@ -25,7 +25,7 @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-cmake_minimum_required (VERSION 3.5)
+cmake_minimum_required (VERSION 3.12)
 # policy CMP0025 is to get AppleClang identifier rather than Clang for both
 # this matters since the apple compiler accepts different flags.
 cmake_policy(SET CMP0025 NEW)

cmake/openssl.cmake

@@ -84,8 +84,9 @@ macro (find_libcrypto)
     endif(WIN32 OR OPENSSL_STATIC_LINK)
 
     message("        OpenSSL version:   ${OPENSSL_VERSION}")
-    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${LIBCRYPTO_CFLAGS}")
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${LIBCRYPTO_CFLAGS}")
+    list(JOIN LIBCRYPTO_CFLAGS " " LIBCRYPTO_CFLAGS_STRING)
+    set(CMAKE_C_FLAGS "${LIBCRYPTO_CFLAGS_STRING} ${CMAKE_C_FLAGS}")
+    set(CMAKE_CXX_FLAGS "${LIBCRYPTO_CFLAGS_STRING} ${CMAKE_CXX_FLAGS}")
     link_directories(${LIBCRYPTO_LIBRARY_DIRS})
     include_directories(${LIBCRYPTO_INCLUDE_DIRS})
 

cmake/pcscd.cmake

@@ -75,7 +75,7 @@ macro (find_pcscd)
         set(ENV{PKG_CONFIG_PATH} "${PCSCLITE_PKG_PATH}:$ENV{PKG_CONFIG_PATH}")
         pkg_check_modules(PCSC REQUIRED libpcsclite)
         if(PCSC_FOUND)
-            set(PCSC_LIBRARIES ${PCSC_LDFLAGS})
+            list(JOIN PCSC_LDFLAGS " " PCSC_LIBRARIES)
             if(VERBOSE_CMAKE)
                 message("PCSC_FOUND: ${PCSC_FOUND}")
                 message("PCSC_LIBRARY_DIRS: ${PCSC_LIBRARY_DIRS}")
@@ -100,8 +100,9 @@ macro (find_pcscd)
         else(${PCSC_DIR} NOT STREQUAL "")
             set(PCSC_CUSTOM_LIBS "-Wl,-l${PCSC_LIB}")
         endif(${PCSC_DIR} NOT STREQUAL "")
-        set(CMAKE_C_FLAGS ${PCSC_CFLAGS} ${CMAKE_C_FLAGS})
-        set(PCSC_LIBRARIES ${PCSC_LIBRARIES} ${PCSC_CUSTOM_LIBS})
+        list(JOIN PCSC_CFLAGS " " PCSC_CFLAGS_STRING)
+        set(CMAKE_C_FLAGS "${PCSC_CFLAGS_STRING} ${CMAKE_C_FLAGS}")
+        set(PCSC_LIBRARIES "${PCSC_LIBRARIES} ${PCSC_CUSTOM_LIBS}")
         unset(PCSC_MACOSX_LIBS)
         unset(PCSC_WIN_LIBS)
         unset(PCSC_LIBS)