Build: Fix bugs in the CMake files.

Seems that the phrase "add more quotes" from sh/bash scripting
applies to CMake as well. E.g. passing an unquoted list ${FOO}
to a function that expects one argument results in only the
first element of the list being passed as an argument and
the rest get ignored. Adding quotes helps ("${FOO}").

list(INSERT ...) is weird. Inserting an empty string to an empty
variable results in empty list, but inserting it to a non-empty
variable does insert an empty element to the list.

Since INSERT requires at least one element,
"${CMAKE_THREAD_LIBS_INIT}" needs to be quoted in CMakeLists.txt.
It might result in an empty element in the list. It seems to not
matter as empty elements consistently get ignored in that variable.
In fact, calling cmake_check_push_state() and cmake_check_pop_state()
will strip the empty elements from CMAKE_REQUIRED_LIBRARIES!

In addition to quoting fixes, this fixes checks for the cache
variables in tuklib_cpucores.cmake and tuklib_physmem.cmake.

Thanks to Martin Matuška for testing and reporting the problems.
These fixes aren't tested yet but hopefully they soon will be.

1 files changed, 5 insertions, 3 deletions

diff --git a/cmake/tuklib_common.cmake b/cmake/tuklib_common.cmake
index c3d2c536..088a3cb1 100644
--- a/cmake/tuklib_common.cmake
+++ b/cmake/tuklib_common.cmake
@@ -8,16 +8,18 @@
 #
 
 function(tuklib_add_definitions TARGET_OR_ALL DEFINITIONS)
+    # DEFINITIONS may be an empty string/list but it's fine here. There is
+    # no need to quote ${DEFINITIONS} as empty arguments are fine here.
     if(TARGET_OR_ALL STREQUAL "ALL")
         add_compile_definitions(${DEFINITIONS})
     else()
-        target_compile_definitions(${TARGET_OR_ALL} PRIVATE ${DEFINITIONS})
+        target_compile_definitions("${TARGET_OR_ALL}" PRIVATE ${DEFINITIONS})
     endif()
 endfunction()
 
 function(tuklib_add_definition_if TARGET_OR_ALL VAR)
     if(${VAR})
-        tuklib_add_definitions(${TARGET_OR_ALL} ${VAR})
+        tuklib_add_definitions("${TARGET_OR_ALL}" "${VAR}")
     endif()
 endfunction()
 
@@ -28,7 +30,7 @@ macro(tuklib_use_system_extensions TARGET_OR_ALL)
         # FIXME? The Solaris-specific __EXTENSIONS__ should be conditional
         #        even on Solaris. See gnulib: git log m4/extensions.m4.
         # FIXME? gnulib and autoconf.git has lots of new stuff.
-        tuklib_add_definitions(${TARGET_OR_ALL}
+        tuklib_add_definitions("${TARGET_OR_ALL}"
             _GNU_SOURCE
             __EXTENSIONS__
             _POSIX_PTHREAD_SEMANTICS