Build issue with Ubuntu

[maekawa-mugi]

make  all-recursive
make[1]: Entering directory '/home/mugi/vreng-9.4.4'
Making all in src
make[2]: Entering directory '/home/mugi/vreng-9.4.4/src'
Making all in base
make[3]: Entering directory '/home/mugi/vreng-9.4.4/src/base'
depbase=`echo nsl.o | sed 's|[^/]*$|.deps/&|;s|\.o$||'`;\
clang++-18 -DHAVE_CONFIG_H -I. -I../..  -I../../src -I/usr/include/libxml2     -I../../src/ai -I../../src/base -I../../src/ubit -I../../src/gui -I../../src/world -I../../src/net -I../../src/2d -I../../src/model -I../../src/3d -I../../src/vnc -I../../src/tool   -g  -Wall -D_REENTRANT -MT nsl.o -MD -MP -MF $depbase.Tpo -c -o nsl.o nsl.cpp &&\
mv -f $depbase.Tpo $depbase.Po
nsl.cpp:41:43: error: expected '(' after 'static_cast'
   41 |   if ((hp =  static_cast<struct hostent *>)malloc(sizeof(struct hostent)))) != NULL)
      |                                           ^
      |                                           (
nsl.cpp:41:75: error: extraneous ')' after condition, expected a statement
   41 |   if ((hp =  static_cast<struct hostent *>)malloc(sizeof(struct hostent)))) != NULL)
      |                                                                           ^
nsl.cpp:41:77: error: expected expression
   41 |   if ((hp =  static_cast<struct hostent *>)malloc(sizeof(struct hostent)))) != NULL)
      |                                                                             ^
nsl.cpp:63:11: error: no matching function for call to 'gethostbyname_r'
   63 |   hptmp = gethostbyname_r(hostname, &result, buf, sizeof(buf), &err);
      |           ^~~~~~~~~~~~~~~
/usr/include/netdb.h:177:12: note: candidate function not viable: requires 6 arguments, but 5 were provided
  177 | extern int gethostbyname_r (const char *__restrict __name,
      |            ^                ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  178 |                             struct hostent *__restrict __result_buf,
      |                             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  179 |                             char *__restrict __buf, size_t __buflen,
      |                             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  180 |                             struct hostent **__restrict __result,
      |                             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  181 |                             int *__restrict __h_errnop);
      |                             ~~~~~~~~~~~~~~~~~~~~~~~~~~
4 errors generated.
make[3]: *** [Makefile:452: nsl.o] Error 1
make[3]: Leaving directory '/home/mugi/vreng-9.4.4/src/base'
make[2]: *** [Makefile:360: all-recursive] Error 1
make[2]: Leaving directory '/home/mugi/vreng-9.4.4/src'
make[1]: *** [Makefile:417: all-recursive] Error 1
make[1]: Leaving directory '/home/mugi/vreng-9.4.4'
make: *** [Makefile:358: all] Error 2

I tried building on Ubuntu 22.04.4 WSL with Clang 18.
Same error on real debian 12.5.0 with GCC.

It doesn't seem to take into account that gethostbyname_r is different for each environment.

[philippedax]

Many thanks for your feedback.

I thinks it's now fixed (commit ff62b13).

Philippe

[maekawa-mugi]

Thank you.
I tried to build it again, but an error occurred if I didn't explicitly cast the argument of gethostbyname_r to int.

When I fixed that, the error still occurred because the library was not included.

Apparently, libraries were not detected correctly in configure.ac, so the library detection method also needs to be corrected.

[philippedax]

Please, which argument ? There are 6 arguments for gethostbyname_r.
Can you send me a trace of compilation ?

The library to be include should be -l nsl

please grep GET.*BYNAME config.h and send me the result.

Thanks

[philippedax]

Oops the library to be included should be libc standard (-lc).

I maintain vreng on a Mac under MacOS-10.13 and I have not gethostbyname_r.

[maekawa-mugi]

nsl.cpp: In function ‘hostent* my_gethostbyname_r(const char*, int)’:
nsl.cpp:67:26: error: invalid conversion from ‘int’ to ‘hostent*’ [-fpermissive]
   67 |   hptmp = gethostbyname_r(hostname, &result, buf, sizeof(buf), &hptmp, &err);
      |           ~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      |                          |
      |                          int
make[3]: *** [Makefile:454: nsl.o] Error 1
make[3]: Leaving directory '/home/mugi/vreng/src/base'
make[2]: *** [Makefile:362: all-recursive] Error 1
make[2]: Leaving directory '/home/mugi/vreng/src'
make[1]: *** [Makefile:419: all-recursive] Error 1
make[1]: Leaving directory '/home/mugi/vreng'
make: *** [Makefile:360: all] Error 2

It seems like the #if block isn't working. After deleting that block, it works, but libraries such as freetype2 are not recognized, so it stops due to that.

[philippedax]

I think I have fixed, but I can't test

struct hostent ret;
struct hostent result;
int r;
int err;
char buf[512];

r = gethostbyname_r(hostname, &ret, buf, sizeof(buf), &result, &err);
if (r == 0)
return result;
else
return NULL;