make[1]: Entering directory `/home/weegee/docs/projekte/c/pontoon/src'
make[1]: warning: jobserver unavailable: using -j1.  Add `+' to parent make rule.
gcc  -o main.o main.c
In file included from main.c:26:0:
ai.h:6:70: warning: 'struct deck' declared inside parameter list [enabled by default]
ai.h:6:70: warning: its scope is only this definition or declaration, which is probably not what you want [enabled by default]
/tmp/ccSh5nJr.o: In function `main':
main.c:(.text+0x3b): undefined reference to `createdeck'
main.c:(.text+0x50): undefined reference to `createdeck'
main.c:(.text+0x60): undefined reference to `showdeck'
main.c:(.text+0x71): undefined reference to `createdeck'
main.c:(.text+0x8d): undefined reference to `game'
collect2: ld returned 1 exit status
make[1]: *** [main.o] Error 1
make[1]: Leaving directory `/home/weegee/docs/projekte/c/pontoon/src'
make: *** [pontoon] Error 2