MVEM Build 15 Linker Error

gcc -o mvem main.c hardware.c core11.c debugsc11.c system.c hwinterface.c -std=c99 -g -O2 -DDEBUGGABLE -D_THREAD_SAFE -I/usr/local/include/SDL2 -I/usr/X11R6/include  -I/usr/X11/include -DHAVE_OPENGL -g
hardware.c: In function ‘IF_Initialise’:
hardware.c:85:5: warning: implicit declaration of function ‘IF_ToggleFullscreen’ [-Wimplicit-function-declaration]
     if (f == 1) IF_ToggleFullscreen();
     ^
hardware.c: At top level:
hardware.c:155:6: warning: conflicting types for ‘IF_ToggleFullscreen’
 void IF_ToggleFullscreen(SDL_Window* Window) {
      ^
hardware.c:85:17: note: previous implicit declaration of ‘IF_ToggleFullscreen’ was here
     if (f == 1) IF_ToggleFullscreen();
                 ^
In file included from core11.c:38:0:
core11.c: In function ‘tms1100reset’:
code11.h:18:31: warning: iteration 128u invokes undefined behavior [-Waggressive-loop-optimizations]
     dataMemory[i] = dataMemory[i] & 0xF;
                               ^
code11.h:17:2: note: containing loop
  for (i = 0;i <= 0x80;i++)
  ^
/tmp/ccSInogM.o: In function `IF_Terminate':
/home/pi/new_mvem/hardware.c:330: undefined reference to `SDL_DestroyRenderer'
/home/pi/new_mvem/hardware.c:331: undefined reference to `SDL_DestroyWindow'
/home/pi/new_mvem/hardware.c:332: undefined reference to `SDL_Quit'
/tmp/ccSInogM.o: In function `IF_ToggleFullscreen':
/home/pi/new_mvem/hardware.c:157: undefined reference to `SDL_GetWindowFlags'
/home/pi/new_mvem/hardware.c:158: undefined reference to `SDL_SetWindowFullscreen'
/home/pi/new_mvem/hardware.c:159: undefined reference to `SDL_FlushEvent'
/tmp/ccSInogM.o: In function `IF_Initialise':
/home/pi/new_mvem/hardware.c:63: undefined reference to `SDL_Init'
/home/pi/new_mvem/hardware.c:76: undefined reference to `SDL_CreateWindow'
/home/pi/new_mvem/hardware.c:78: undefined reference to `SDL_CreateRenderer'
/home/pi/new_mvem/hardware.c:79: undefined reference to `SDL_SetRelativeMouseMode'
/home/pi/new_mvem/hardware.c:95: undefined reference to `SDL_OpenAudio'
/home/pi/new_mvem/hardware.c:64: undefined reference to `SDL_GetError'
/tmp/ccSInogM.o: In function `IF_LoadOverlay':
/home/pi/new_mvem/hardware.c:169: undefined reference to `SDL_SetHint'
/home/pi/new_mvem/hardware.c:173: undefined reference to `SDL_RWFromFile'
/home/pi/new_mvem/hardware.c:173: undefined reference to `SDL_LoadBMP_RW'
/home/pi/new_mvem/hardware.c:175: undefined reference to `SDL_CreateTextureFromSurface'
/home/pi/new_mvem/hardware.c:179: undefined reference to `SDL_RWFromFile'
/home/pi/new_mvem/hardware.c:179: undefined reference to `SDL_LoadBMP_RW'
/home/pi/new_mvem/hardware.c:181: undefined reference to `SDL_CreateTextureFromSurface'
/home/pi/new_mvem/hardware.c:186: undefined reference to `SDL_RWFromFile'
/home/pi/new_mvem/hardware.c:186: undefined reference to `SDL_LoadBMP_RW'
/home/pi/new_mvem/hardware.c:188: undefined reference to `SDL_CreateTextureFromSurface'
/home/pi/new_mvem/hardware.c:191: undefined reference to `SDL_RWFromFile'
/home/pi/new_mvem/hardware.c:191: undefined reference to `SDL_LoadBMP_RW'
/home/pi/new_mvem/hardware.c:193: undefined reference to `SDL_CreateTextureFromSurface'
/tmp/ccSInogM.o: In function `IF_RenderScreen':
/home/pi/new_mvem/hardware.c:213: undefined reference to `SDL_SetRenderDrawColor'
/home/pi/new_mvem/hardware.c:214: undefined reference to `SDL_RenderFillRect'
/home/pi/new_mvem/hardware.c:215: undefined reference to `SDL_SetRenderDrawColor'
/home/pi/new_mvem/hardware.c:224: undefined reference to `SDL_RenderFillRect'
/home/pi/new_mvem/hardware.c:227: undefined reference to `SDL_RenderDrawRect'
/home/pi/new_mvem/hardware.c:242: undefined reference to `SDL_RenderCopy'
/home/pi/new_mvem/hardware.c:258: undefined reference to `SDL_RenderCopy'
/home/pi/new_mvem/hardware.c:259: undefined reference to `SDL_RenderCopy'
/home/pi/new_mvem/hardware.c:268: undefined reference to `SDL_SetRenderDrawBlendMode'
/home/pi/new_mvem/hardware.c:270: undefined reference to `SDL_SetRenderDrawColor'
/home/pi/new_mvem/hardware.c:271: undefined reference to `SDL_RenderFillRect'
/home/pi/new_mvem/hardware.c:281: undefined reference to `SDL_RenderCopyEx'
/home/pi/new_mvem/hardware.c:286: undefined reference to `SDL_SetRenderDrawColor'
/home/pi/new_mvem/hardware.c:287: undefined reference to `SDL_RenderFillRect'
/home/pi/new_mvem/hardware.c:270: undefined reference to `SDL_SetRenderDrawColor'
/home/pi/new_mvem/hardware.c:271: undefined reference to `SDL_RenderFillRect'
/tmp/ccSInogM.o: In function `IF_Render':
/home/pi/new_mvem/hardware.c:110: undefined reference to `SDL_PollEvent'
/home/pi/new_mvem/hardware.c:110: undefined reference to `SDL_PollEvent'
/home/pi/new_mvem/hardware.c:143: undefined reference to `SDL_SetRenderDrawColor'
/home/pi/new_mvem/hardware.c:144: undefined reference to `SDL_RenderClear'
/home/pi/new_mvem/hardware.c:147: undefined reference to `SDL_RenderPresent'
/tmp/ccSInogM.o: In function `IF_Write':
/home/pi/new_mvem/hardware.c:301: undefined reference to `SDL_SetRenderDrawColor'
/home/pi/new_mvem/hardware.c:302: undefined reference to `SDL_RenderFillRect'
/home/pi/new_mvem/hardware.c:308: undefined reference to `SDL_SetRenderDrawColor'
/home/pi/new_mvem/hardware.c:318: undefined reference to `SDL_RenderFillRect'
/tmp/ccSInogM.o: In function `IF_SetSound':
/home/pi/new_mvem/hardware.c:355: undefined reference to `SDL_PauseAudio'
/tmp/ccSInogM.o: In function `IF_GetTime':
/home/pi/new_mvem/hardware.c:386: undefined reference to `SDL_GetTicks'
/home/pi/new_mvem/hardware.c:386: undefined reference to `SDL_GetTicks'
/home/pi/new_mvem/hardware.c:386: undefined reference to `SDL_GetTicks'
/home/pi/new_mvem/hardware.c:386: undefined reference to `SDL_GetTicks'
/tmp/ccSInogM.o: In function `IF_SetSound':
/home/pi/new_mvem/hardware.c:355: undefined reference to `SDL_PauseAudio'
/home/pi/new_mvem/hardware.c:355: undefined reference to `SDL_PauseAudio'
collect2: error: ld returned 1 exit status
Makefile:11: recipe for target 'mvem' failed
make: *** [mvem] Error 1