[CMake] Generating Source Files

[Jeremy Cowgar]

Bill Hoffman wrote:
> So, you create a custom command that runs your parser and creates a 
> full CMakeLists.txt file to build the output of the parser.  Then run 
> ctest --build-and-test on that directory to build the parser output.   
> What is the output of the parser?  Is it a program or a library, or both?

The output of the parser is simply .c/.h files that are then compiled 
with CMake to create the executable (linked with other existing .c/.h 
files and libs).

I do not want to require CMake CVS, because I want people who download 
my app to be able to compile the sources. I do not want them to have to 
install CVS copies of CMake. Here is how it works from the command line...

$ euc -outdir interpreter parser.e
... builds ...
$ ls interpreter
parser.c main.c main.h regex.c sequence.c value.c
$

The translator/generator always generates main.c. So, I can depend on 
that. But the others I must dynamically place into a CMake variable for 
later use as:

ADD_EXECUTABLE( myapp ${GENERATED_SOURCE_LIST} )

That's all I am doing. The original CMake file I wrote did a FILE( GLOB 
GENERATED_SOURCE_LIST interpreter/*.c ) ... and this worked fine if you 
invoked make twice. i.e. the first time it saw that a custom command 
needed to be run, it ran it. However, the FILE( GLOB ... ) was empty 
because it ran before the generator ran. Thus, the compile failed 
because of all sorts of missing files. Run make again, and this time the 
FILE( GLOB ... ) was populated correctly because the C files where in 
the dir. The app the builds great.

Jeremy