The try_compile command builds the cmTryCompileExec executable using the
cmTryCompileExec/fast target with Makefile generators in order to save
time since dependencies are not needed. However, in project mode the
command builds an entire source tree that may have dependencies.
Therefore we can use the /fast target approach only in one-source mode.
The try_compile command project mode builds an entire source tree
instead of one source file. It uses an existing CMakeLists.txt file in
the given source tree instead of generating one. This commit creates a
test for the mode in the TryCompile test.
check_c_source_compiles() and check_cxx_source_compiles()
-TRY_RUN in crosscompiling mode: copy the created executables to
CMAKE_BINARY_DIR so the user can run them manually on the target
Alex
creates two cache variables, one for the RUN_RESULT, one for the RUN_OUTPUT
(if required), which can be set or preset by the user. It has now also two
new arguments: RUN_OUTPUT_VARIABLE and COMPILE_OUTPUT_VARIABLE (the old
OUTPUT_VARIABLE merges both), so if only COMPILE_OUTPUT_VARIABLE is used the
run time output of the TRY_RUN is unused and the user doesn't have to care
about the output when crosscompiling. This is now used in FindThreads.cmake,
CheckC/CXXSourceRuns.cmake and TestBigEndian.cmake, which used the output
only for the logfile (compile output is still there). Test/TryCompile/ now
also tests the behaviour of OUTPUT_VARIABLE, RUN_OUTPUT_VARIABLE and
COMPILE_OUTPUT_VARIABLE.
Alex
STYLE: create a new base class cmCoreTryCompile, from which
cmTryCompileCommand and cmTryRunCommand are derived, so there are no public
static functions with lots of arguments anymore
Alex