rm -rf bit-crusher.lv2
mkdir bit-crusher.lv2
gcc -shared -fPIC -DPIC src/bit-crusher.c src/lv2.c -o bit-crusher.lv2/bit-crusher.so
In file included from src/lv2.c:42:
src/instantiate.h: In function 'instantiate_mono':
src/instantiate.h:16:46: warning: implicit declaration of function 'malloc' [-Wimplicit-function-declaration]
   16 |         Plugin_MONO *plugin = (Plugin_MONO *)malloc(sizeof(Plugin_MONO));
      |                                              ^~~~~~
src/instantiate.h:1:1: note: include '<stdlib.h>' or provide a declaration of 'malloc'
  +++ |+#include <stdlib.h>
    1 | /*
src/instantiate.h:16:46: warning: incompatible implicit declaration of built-in function 'malloc' [-Wbuiltin-declaration-mismatch]
   16 |         Plugin_MONO *plugin = (Plugin_MONO *)malloc(sizeof(Plugin_MONO));
      |                                              ^~~~~~
src/instantiate.h:16:46: note: include '<stdlib.h>' or provide a declaration of 'malloc'
src/instantiate.h: In function 'instantiate_stereo':
src/instantiate.h:27:50: warning: incompatible implicit declaration of built-in function 'malloc' [-Wbuiltin-declaration-mismatch]
   27 |         Plugin_STEREO *plugin = (Plugin_STEREO *)malloc(sizeof(Plugin_STEREO));
      |                                                  ^~~~~~
src/instantiate.h:27:50: note: include '<stdlib.h>' or provide a declaration of 'malloc'
In file included from src/lv2.c:69:
src/cleanup.h: In function 'cleanup_mono':
src/cleanup.h:14:9: warning: implicit declaration of function 'free' [-Wimplicit-function-declaration]
   14 |         free( plugin->state );
      |         ^~~~
src/cleanup.h:1:1: note: include '<stdlib.h>' or provide a declaration of 'free'
  +++ |+#include <stdlib.h>
    1 | /*
src/cleanup.h:14:9: warning: incompatible implicit declaration of built-in function 'free' [-Wbuiltin-declaration-mismatch]
   14 |         free( plugin->state );
      |         ^~~~
src/cleanup.h:14:9: note: include '<stdlib.h>' or provide a declaration of 'free'
src/cleanup.h: In function 'cleanup_stereo':
src/cleanup.h:21:9: warning: incompatible implicit declaration of built-in function 'free' [-Wbuiltin-declaration-mismatch]
   21 |         free( plugin->state_l );
      |         ^~~~
src/cleanup.h:21:9: note: include '<stdlib.h>' or provide a declaration of 'free'
src/lv2.c: At top level:
src/lv2.c:77:9: error: 'NULL' undeclared here (not in a function)
   77 |         NULL,
      |         ^~~~
src/lv2.c:70:1: note: 'NULL' is defined in header '<stddef.h>'; did you forget to '#include <stddef.h>'?
   69 | #include "cleanup.h"
  +++ |+#include <stddef.h>
   70 | 
make: *** [Makefile:9: lv2] Error 1

lilv_lib_open(): error: Failed to open library /usr/lib/lv2/bit-crusher.lv2/bit-crusher.so (/usr/lib/lv2/bit-crusher.lv2/bit-crusher.so: undefined symbol: prepare_downsampling_knob)

Notice: could not set realtime priority.
VST sync support disabled in your configuration
[1]    2766 segmentation fault (core dumped)  lmms