Makefile error ignored

For example on a system without cc (but still having a C Compiler):

==> captcha
rm -f priv/captcha src/captcha.o 
cc -g   -c -o src/captcha.o src/captcha.c
make: cc: No such file or directory
make: *** [<builtin>: src/captcha.o] Error 127

Compiling 1 file (.ex)
Generated captcha app