[CMake] Generating Source Files

[Jeremy Cowgar]

Bill Hoffman wrote:
> If the included file is newer than the last run of cmake, cmake will 
> re-run during make.   In your code, it looks like you write two 
> different files:
>
> "${CMAKE_SOURCE_DIR}/int.ex"
> and
> "${CMAKE_SOURCE_DIR}/interpreter/int.cmake"
>
> I don't get it...

I don't write int.ex, that is what is translated. That is the main 
source for the interpreter. Now, when int.ex is translated, int.cmake is 
updated. Now, this is the problem, or the disconnect..... int.cmake is 
NOT updated when I run wmake. The EXECUTE_PROCESS call is what causes 
int.cmake to be updated. What is updated is, parser.e. Let me run 
through this...

1. I run cmake -G "Watcom WMake" ..

That sees that int.cmake does not exist, and it causes the 
EXECUTE_PROCESS to run, which generates all sorts of C files as well as 
int.cmake.

2. I run wmake

This makes my project and everything is great.

3. I edit ../source/parser.e and add new functionality. This file 
../source/parser.e is listed in EU_CORE_FILES, which is checked in a 
FOREACH loop as to if it's newer or not than int.cmake. (See my 
FOREACH/EXECUTE_PROCESS below)

Now, here is where the problem starts. the int.cmake file is not 
updated. I only updated parser.e However, I was expecting this to see 
that parser.e is newer than int.cmake and cause EXECUTE_PROCESS to run 
again, causing int.cmake to be updated. (See my FOREACH/EXECUTE_PROCESS 
below)

4. Once done making changes to my project (parser.e is just one of many 
files, but I keep using it as an example of what I edit), I run wmake. 
However, int.cmake has not been updated at this point, still. I expected 
that the FOREACH loop would detect that parser.e is newer than int.cmake 
and cause the EXECUTE_PROCESS to translate my code again:

FOREACH( file ${EU_CORE_FILES} )
  IF( "${CMAKE_SOURCE_DIR}/source/${file}" IS_NEWER_THAN 
"${CMAKE_CURRENT_BINARY_DIR}/int.cmake" )
    SET( EU_CORE_UPDATE 1 )
  ENDIF()
ENDFOREACH()

IF( EU_CORE_UPDATE )
  MESSAGE( "Translating interpreter..." )
  EXECUTE_PROCESS(
    COMMAND ${TRANSLATOR} -cmakefile "${CMAKE_SOURCE_DIR}/source/int.ex"
    WORKING_DIR ${CMAKE_CURRENT_BINARY_DIR} )
ENDIF()


Does that make it any clearer? I know I am just not describing my 
process well enough, but I am trying.

Jeremy