It does not compile

I am compiling this on Debian Testing 64bit

px.o: In function `fbClear':
/DRIVE/gc/px/px.c:128: undefined reference to`glClear'
/DRIVE/gc/px/px.c:129: undefined reference to `glClearColor'
px.o: In function`spriteResizeFrame':
/DRIVE/gc/px/px.c:230: undefined reference to `glDeleteTextures'
px.o: In function`spriteReadPixels':
/DRIVE/gc/px/px.c:277: undefined reference to `glBindFramebuffer'
/DRIVE/gc/px/px.c:278: undefined reference to`glReadPixels'
/DRIVE/gc/px/px.c:279: undefined reference to `glBindFramebuffer'
px.o: In function`createFrame':
/DRIVE/gc/px/px.c:298: undefined reference to `glDeleteTextures'
/DRIVE/gc/px/px.c:303: undefined reference to`glBindFramebuffer'
/DRIVE/gc/px/px.c:304: undefined reference to `glDrawPixels'
/DRIVE/gc/px/px.c:305: undefined reference to`glBlitFramebuffer'
/DRIVE/gc/px/px.c:312: undefined reference to `glBindFramebuffer'
px.o: In function`sample':
/DRIVE/gc/px/px.c:528: undefined reference to `glReadPixels'
px.o: In function`spriteFlash':
/DRIVE/gc/px/px.c:173: undefined reference to `glBindFramebuffer'
/DRIVE/gc/px/px.c:174: undefined reference to`glClear'
/DRIVE/gc/px/px.c:175: undefined reference to `glClearColor'
/DRIVE/gc/px/px.c:176: undefined reference to`glBindFramebuffer'
px.o: In function `spriteRestoreSnapshot':
/DRIVE/gc/px/px.c:185: undefined reference to`glBindFramebuffer'
/DRIVE/gc/px/px.c:186: undefined reference to `glClear'
/DRIVE/gc/px/px.c:187: undefined reference to`glClearColor'
/DRIVE/gc/px/px.c:188: undefined reference to `glDrawPixels'
/DRIVE/gc/px/px.c:189: undefined reference to`glBindFramebuffer'
clang: error: linker command failed with exit code 1 (use -v to see invocation)
Reaping losing child 0x2132500 PID 26190
Makefile:15: recipe for target 'px' failed
make: **\* [px] Error 1
Removing child 0x2132500 PID 26190 from chain.