Should now build under Linux.

src/os/unix/CMakeLists.txt

@@ -11,4 +11,4 @@
 
 add_library(oslib loadfile.c graphics.c sound.c io.c)
 
-target_link_libraries(oslib glfw ${OPENGL_glu_LIBRARY})
+target_link_libraries(oslib glfw ${OPENGL_glu_LIBRARY} ${OPENGL_gl_LIBRARY})

src/os/unix/graphics.c

@@ -19,7 +19,7 @@
 #include <os_dependent.h>
 
 #include <GLFW/glfw3.h>
-#include <OpenGL/glext.h>
+//#include <OpenGL/glext.h>
 
 #include <palette.h>
 
@@ -433,4 +433,4 @@ int graphics_blit(long x, long y, long w, long h)
 int getKeyStatus(int key)
 {
    return mainWindow.keyArray[key].curState;
-}
+}

src/ppu/debug/ppu.debug.c

@@ -15,6 +15,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 
+#if 0
 /* Allegro includes */
 #ifdef __APPLE__
 #define USE_CONSOLE
@@ -367,3 +368,4 @@ void ppu_dumpPalette(int x, int y)
         rectfill(Buffer, x + 91 + (i % 4) * 20, y + 21 +(i / 4) * 20, x + 91 + (i % 4) * 20 + 20, y + 21 +(i / 4) * 20 + 20, ppu_readMemory(0x3F, i+0x10));
     }
 }
+#endif