Re: [lwip-devel] Building using MinGW

[Simon Goldschmidt]

Gisle Vanem wrote:
> Trying to build lwIP using TDM-gcc 5.1.0 (MinGW), now produces
> this error:
>    In file included from f:/MingW32/src/inet/libpcap/pcap/pcap.h:74:0,
>                     from f:/MingW32/src/inet/libpcap/pcap.h:43,
>                     from contrib/ports/win32/pcapif.c:50:
>    f:/MingW32/src/inet/libpcap/pcap/pcap-inttypes.h:48:6: error: #error 
> "Building libpcap
> requires VS 2015 or   later"
>         #error "Building libpcap requires VS 2015 or later"
>          ^
>
>
> The cause of this is the "define _MSC_VER 1500" in pcapif.c:
>    /* e.g. mingw */
>    #define _MSC_VER 1500
>    #include "pcap.h"
>    #undef _MSC_VER
>
> Bumping '_MSC_VER' to 1900 fixes this. But why are these lines needed?

Hmm, I really can't remember. Probably because the pcap sources I used at that
time did not work without defining it? I don't think mingw defines _MSC_VER, and
since the pcap headers do different things without it, this made it work.

But I'm not using mingw, so that #else case in pcapif.c is probably not used by
anyone right now. Feel free to get it compiling for you in the best way and
provide a patch :)

Regards,
Simon