Re: [lwip-devel] Can't compile due to unknown memory functions

[address@hidden]

address@hidden wrote:
> I've some troubles in compiling v1.4.0. I get several errors about unknown 
> memory functions like
>
> lwip-1.4.0/src/core/init.c:270: undefined reference to `mem_init'
> lwip-1.4.0/src/core/init.c:271: undefined reference to `memp_init'
> lwip-1.4.0/src/core/init.c:304: undefined reference to `sys_timeouts_init'
Seems like you forgot to compile and link mem.c, memp.c and timers.c?
> Now when I change my lwiopts.h and add a statement
>
> #define MEM_LIBC_MALLOC             1
>
> there, the erros change to
>
> lwip-1.4.0/src/core/pbuf.c:286:17: error: implicit declaration of function 
> 'malloc'
> lwip-1.4.0/src/core/pbuf.c:286:23: error: incompatible implicit declaration of 
> built-in function 'malloc
> lwip-1.4.0/src/core/pbuf.c:654:11: error: implicit declaration of function 
> 'free'
> lwip-1.4.0/src/core/pbuf.c:654:11: error: incompatible implicit declaration of 
> built-in function 'free'
>
> What could be the reason for this? Which switches do I have to set to use 
> malloc()/free() based memory functions?

Since not all (embedded) compilers have malloc/free defined in the same 
header files, we don't include them when setting MEM_LIBC_MALLOC to 1. 
Place an include to the correct header file somewhere (e.g. in cc.h).

Simon