error: Cannot build '/nix/store/gm5win3imb4ira9xihqjgmkw6grwwz96-flex-x86_64-unknown-freebsd-2.6.4.drv'.
       Reason: builder failed with exit code 2.
       Output paths:
         /nix/store/2zahnxwrgj39cs2asrwgi0hm7bjilknw-flex-x86_64-unknown-freebsd-2.6.4
       Last 25 log lines:
       > gcc -DHAVE_CONFIG_H -I.  -DLOCALEDIR=\"/nix/store/2zahnxwrgj39cs2asrwgi0hm7bjilknw-flex-x86_64-unknown-freebsd-2.6.4/share/locale\"   -g -O2 -c -o stage1flex-sym.o `test -f 'sym.c' || echo './'`sym.c
       > gcc -DHAVE_CONFIG_H -I.  -DLOCALEDIR=\"/nix/store/2zahnxwrgj39cs2asrwgi0hm7bjilknw-flex-x86_64-unknown-freebsd-2.6.4/share/locale\"   -g -O2 -c -o stage1flex-tables.o `test -f 'tables.c' || echo './'`tables.c
       > gcc -DHAVE_CONFIG_H -I.  -DLOCALEDIR=\"/nix/store/2zahnxwrgj39cs2asrwgi0hm7bjilknw-flex-x86_64-unknown-freebsd-2.6.4/share/locale\"   -g -O2 -c -o stage1flex-tables_shared.o `test -f 'tables_shared.c' || echo './'`tables_shared.c
       > gcc -DHAVE_CONFIG_H -I.  -DLOCALEDIR=\"/nix/store/2zahnxwrgj39cs2asrwgi0hm7bjilknw-flex-x86_64-unknown-freebsd-2.6.4/share/locale\"   -g -O2 -c -o stage1flex-tblcmp.o `test -f 'tblcmp.c' || echo './'`tblcmp.c
       > gcc -DHAVE_CONFIG_H -I.  -DLOCALEDIR=\"/nix/store/2zahnxwrgj39cs2asrwgi0hm7bjilknw-flex-x86_64-unknown-freebsd-2.6.4/share/locale\"   -g -O2 -c -o stage1flex-yylex.o `test -f 'yylex.c' || echo './'`yylex.c
       > gcc -DHAVE_CONFIG_H -I.  -DLOCALEDIR=\"/nix/store/2zahnxwrgj39cs2asrwgi0hm7bjilknw-flex-x86_64-unknown-freebsd-2.6.4/share/locale\"   -g -O2 -c -o ../lib/stage1flex-malloc.o `test -f '../lib/malloc.c' || echo './'`../lib/malloc.c
       > ../lib/malloc.c:6:12: warning: conflicting types for built-in function 'malloc'; expected 'void *(long unsigned int)' [-Wbuiltin-declaration-mismatch]
       >     6 |      void *malloc ();
       >       |            ^~~~~~
       > ../lib/malloc.c:5:1: note: 'malloc' is declared in header '<stdlib.h>'
       >     4 |      #include <sys/types.h>
       >   +++ |+#include <stdlib.h>
       >     5 |
       > ../lib/malloc.c: In function 'rpl_malloc':
       > ../lib/malloc.c:16:15: error: too many arguments to function 'malloc'; expected 0, have 1
       >    16 |        return malloc (n);
       >       |               ^~~~~~  ~
       > ../lib/malloc.c:6:12: note: declared here
       >     6 |      void *malloc ();
       >       |            ^~~~~~
       > make[2]: *** [Makefile:1448: ../lib/stage1flex-malloc.o] Error 1
       > make[2]: Leaving directory '/build/flex-2.6.4/src'
       > make[1]: *** [Makefile:581: all] Error 2
       > make[1]: Leaving directory '/build/flex-2.6.4/src'
       > make: *** [Makefile:543: all-recursive] Error 1