Autodetect source for automake

Question

I'm trying to do a Makefile.am who find all the dependency (c and cpp files) at runtime (make).

I test this command :

example_SOURCES=$(shell find . -type f | grep -E '\.c|\.cpp' | awk '{L[NR]=$$0} END {{for (i = 1; i <=NR-1;i++) print L[i]"\\"}; {print L[NR]}}')

The command works fine ( I have controlled with the add of a redirection in a file and the sources are fine).

But the makefile, doesn't use any sources :

gcc  -g -O2    -o example 

How can I archive my objective for auto-founds all sources ?

ps I have read that automake must know all sources at call, this is correct ? This can be an explanation why my script doesn't work.

More details : I have modify the Makefile generate and place an echo on example_sources and he contain all my files.

I have check the differences between the Makefile with my script and without and the main point is this part :

With script :

am_example_OBJECTS =

With manual dependency :

am_example_OBJECTS = ./main.$(OBJEXT)

He appear the automake need to know the sources files himself for generate the makefile.

Answer 1

So I have found a workaround,

I use a sed to change the Makefile.am during the configure.

# Source + dependency.
files=`find ./src/ -type f | grep -E '\.h$$|\.hpp$$|\.c$$|\.cpp$$' | sed 's/\/src//g'` 
sed -i '/.*_SOURCES.*/c\'"$soft"'_SOURCES = '"$files"'' src/Makefile.am

It's work fine, when we add sources, we just need to do ./configure to update the dependency list.