Question

I have a makefile, which is missing an ldflag. I know how to fix it, but I don’t know which line in the makefile the error is generated on.

+ make
  CCLD   test
test-test.o: In function `write_png':
/home/lenovo/scratch/libass/test/test.c:52: undefined reference to `png_create_write_struct'
...
/home/lenovo/scratch/libass/test/test.c:57: undefined reference to `png_destroy_write_struct'
collect2: ld returned 1 exit status
make: *** [test] Error 1

How do I get make to print out the line the error is on?

(If anybody is wondering, it is a makefile from the libass project in the test directory.)

Answer 1

Try using remake to see if it helps.

http://static.usenix.org/events/lisa11/tech/full_papers/Bernstein.pdf

Heres an example obtained from the link above:

Hope this helps!