Fix a couple of warnings in C code.

This commit fixes the list of warnings below.
They have been obtained while compiling the MinGW port with gcc version
4.9.2.

A few remarks are due:

1. Several warnings are about the _WIN32_WINNT macro. This commit gets
rid of those warnings by #undef-ing the macro in those files that define
it anyway.

2. In win32graph/draw.c, the function caml_gr_show_bitmap which causes a
warning has been removed, because this (broken) code is actually not
called by any other function. It turned out that all the functions
defined in the win32graph/dib.c module are unused, too. This dib.c
module has thus been removed completely.

3. The warnings about variables that might be used without having been
previously initialised occur because the C compiler does not realise
that unix_error never returns. So, fixing this warning does not require
any modification of the source files where it occurs. It rather requires
to declare that unix_error does not return on Windows, as is actually
already done on Unix.

List of fixed warnings :

asmrun/clambda_checks.c:
clambda_checks.c: In function ‘caml_check_field_access’:
clambda_checks.c:62:7: warning: unknown conversion type character ‘l’ in format [-Wformat=]
       (ARCH_UINT64_TYPE) Long_val(pos), descr);
       ^
clambda_checks.c:62:7: warning: format ‘%s’ expects argument of type ‘char *’, but argument 3 has type ‘long long unsigned int’ [-Wformat=]
clambda_checks.c:62:7: warning: too many arguments for format [-Wformat-extra-args]
clambda_checks.c:68:7: warning: unknown conversion type character ‘l’ in format [-Wformat=]
       (ARCH_UINT64_TYPE) Long_val(pos), (void*) v, descr);
       ^
clambda_checks.c:68:7: warning: format ‘%p’ expects argument of type ‘void *’, but argument 3 has type ‘long long unsigned int’ [-Wformat=]
clambda_checks.c:68:7: warning: format ‘%s’ expects argument of type ‘char *’, but argument 4 has type ‘void *’ [-Wformat=]
clambda_checks.c:68:7: warning: too many arguments for format [-Wformat-extra-args]
clambda_checks.c:82:7: warning: unknown conversion type character ‘l’ in format [-Wformat=]
       descr);
       ^
clambda_checks.c:82:7: warning: format ‘%p’ expects argument of type ‘void *’, but argument 3 has type ‘long long unsigned int’ [-Wformat=]
clambda_checks.c:82:7: warning: unknown conversion type character ‘l’ in format [-Wformat=]
clambda_checks.c:82:7: warning: format ‘%s’ expects argument of type ‘char *’, but argument 4 has type ‘void *’ [-Wformat=]
clambda_checks.c:82:7: warning: too many arguments for format [-Wformat-extra-args]
otherlibs/win32unix/createprocess.c:
createprocess.c: In function ‘win_create_process_native’:
createprocess.c:66:5: warning: implicit declaration of function ‘caml_stat_free’ [-Wimplicit-function-declaration]
     caml_stat_free(exefile);
     ^
otherlibs/win32unix/select.c:
In file included from select.c:21:0:
winworker.h:19:0: warning: "_WIN32_WINNT" redefined
 #define _WIN32_WINNT 0x0400
 ^
In file included from /usr/i686-w64-mingw32/sys-root/mingw/include/crtdefs.h:10:0,
                 from /usr/i686-w64-mingw32/sys-root/mingw/include/stdint.h:28,
                 from /usr/lib/gcc/i686-w64-mingw32/4.9.2/include/stdint.h:9,
                 from ../../byterun/caml/config.h:34,
                 from ../../byterun/caml/mlvalues.h:22,
                 from select.c:16:
/usr/i686-w64-mingw32/sys-root/mingw/include/_mingw.h:225:0: note: this is the location of the previous definition
 #define _WIN32_WINNT 0x502
 ^
select.c: In function ‘find_handle’:
select.c:906:3: warning: enumeration value ‘SELECT_MODE_NONE’ not handled in switch [-Wswitch]
   switch( iterResult->EMode )
   ^
select.c: In function ‘unix_select’:
select.c:1267:19: warning: enumeration value ‘SELECT_MODE_NONE’ not handled in switch [-Wswitch]
                   switch (iterResult->EMode)
                   ^
otherlibs/win32unix/sockopt.c:
sockopt.c: In function ‘unix_setsockopt_aux’:
sockopt.c:200:7: warning: ‘optsize’ may be used uninitialized in this function [-Wmaybe-uninitialized]
   if (setsockopt(Socket_val(socket), level, option,
       ^
otherlibs/win32unix/startup.cstartup.c:
In file included from startup.c:20:0:
winworker.h:19:0: warning: "_WIN32_WINNT" redefined
 #define _WIN32_WINNT 0x0400
 ^
In file included from /usr/i686-w64-mingw32/sys-root/mingw/include/crtdefs.h:10:0,
                 from /usr/i686-w64-mingw32/sys-root/mingw/include/stdio.h:9,
                 from startup.c:16:
/usr/i686-w64-mingw32/sys-root/mingw/include/_mingw.h:225:0: note: this is the location of the previous definition
 #define _WIN32_WINNT 0x502
 ^
otherlibs/win32unix/winworker.c
In file included from winworker.c:20:0:
winworker.h:19:0: warning: "_WIN32_WINNT" redefined
 #define _WIN32_WINNT 0x0400
 ^
In file included from /usr/i686-w64-mingw32/sys-root/mingw/include/crtdefs.h:10:0,
                 from /usr/i686-w64-mingw32/sys-root/mingw/include/stdint.h:28,
                 from /usr/lib/gcc/i686-w64-mingw32/4.9.2/include/stdint.h:9,
                 from ../../byterun/caml/config.h:34,
                 from ../../byterun/caml/mlvalues.h:22,
                 from winworker.c:16:
/usr/i686-w64-mingw32/sys-root/mingw/include/_mingw.h:225:0: note: this is the location of the previous definition
 #define _WIN32_WINNT 0x502
 ^
otherlibs/unix/access.c:
access.c:36:0: warning: "X_OK" redefined
 #  define X_OK    4/* test for execute permission - not implemented in Win32 */
 ^
In file included from /usr/i686-w64-mingw32/sys-root/mingw/include/direct.h:10:0,
                 from unixsupport.h:23,
                 from access.c:20:
/usr/i686-w64-mingw32/sys-root/mingw/include/io.h:174:0: note: this is the location of the previous definition
 #define X_OK 1 /* Check for execute permission. */
 ^
otherlibs/unix/socketaddr.c:
socketaddr.c: In function ‘alloc_sockaddr’:
socketaddr.c:153:3: warning: ‘res’ may be used uninitialized in this function [-Wmaybe-uninitialized]
   return res;
   ^
otherlibs/win32graph/open.c:
open.c: In function ‘caml_gr_open_graph’:
open.c:270:18: warning: pointer targets in passing argument 6 of ‘CreateThread’ differ in signedness [-Wpointer-sign]
                  &tid);
                  ^
In file included from /usr/i686-w64-mingw32/sys-root/mingw/include/winbase.h:29:0,
                 from /usr/i686-w64-mingw32/sys-root/mingw/include/windows.h:70,
                 from libgraph.h:17,
                 from open.c:20:
/usr/i686-w64-mingw32/sys-root/mingw/include/processthreadsapi.h:160:28: note: expected ‘LPDWORD’ but argument is of type ‘long int *’
   WINBASEAPI HANDLE WINAPI CreateThread (LPSECURITY_ATTRIBUTES lpThreadAttributes, SIZE_T dwStackSize, LPTHREAD_START_ROUTINE lpStartAddress, LPVOID lpParameter, DWORD dwCreationFlags, LPDWORD lpThreadId);
                            ^
otherlibs/win32graph/draw.c:
draw.c: In function ‘caml_gr_show_bitmap’:
draw.c:309:9: warning: implicit declaration of function ‘AfficheBitmap’ [-Wimplicit-function-declaration]
         AfficheBitmap(filename,grwindow.gcBitmap,x,Wcvt(y));
         ^
otherlibs/systhreads/st_stubs.c:
In file included from st_stubs.c:50:0:
st_win32.h:18:0: warning: "_WIN32_WINNT" redefined
 #define _WIN32_WINNT 0x0400
 ^
In file included from /usr/i686-w64-mingw32/sys-root/mingw/include/crtdefs.h:10:0,
                 from /usr/i686-w64-mingw32/sys-root/mingw/include/stdint.h:28,
                 from /usr/lib/gcc/i686-w64-mingw32/4.9.2/include/stdint.h:9,
                 from ../../byterun/caml/config.h:34,
                 from ../../byterun/caml/misc.h:24,
                 from ../../byterun/caml/alloc.h:23,
                 from st_stubs.c:18:
/usr/i686-w64-mingw32/sys-root/mingw/include/_mingw.h:225:0: note: this is the location of the previous definition
 #define _WIN32_WINNT 0x502
 ^

1 files changed, 7 insertions, 4 deletions

diff --git a/asmrun/clambda_checks.c b/asmrun/clambda_checks.c
index 7409fa1dad..1d25ecbc4f 100644
--- a/asmrun/clambda_checks.c
+++ b/asmrun/clambda_checks.c
@@ -58,13 +58,15 @@ value caml_check_field_access(value v, value pos, value v_descr)
   const char* descr = String_val(v_descr);
   value orig_v = v;
   if (v == (value) 0) {
-    fprintf(stderr, "Access to field %lld of NULL: %s\n",
-      (ARCH_UINT64_TYPE) Long_val(pos), descr);
+    fprintf(stderr,
+      "Access to field %" ARCH_INT64_PRINTF_FORMAT
+      "u of NULL: %s\n", (ARCH_UINT64_TYPE) Long_val(pos), descr);
     abort();
   }
   if (!Is_block(v)) {
     fprintf(stderr,
-      "Access to field %lld of non-boxed value %p is illegal: %s\n",
+      "Access to field %" ARCH_INT64_PRINTF_FORMAT
+      "u of non-boxed value %p is illegal: %s\n",
       (ARCH_UINT64_TYPE) Long_val(pos), (void*) v, descr);
     abort();
   }
@@ -76,7 +78,8 @@ value caml_check_field_access(value v, value pos, value v_descr)
   assert(Long_val(pos) >= 0);
   if (Long_val(pos) >= Wosize_val(v)) {
     fprintf(stderr,
-      "Access to field %lld of value %p of size %lld is illegal: %s\n",
+      "Access to field %" ARCH_INT64_PRINTF_FORMAT
+      "u of value %p of size %" ARCH_INT64_PRINTF_FORMAT "u is illegal: %s\n",
       (ARCH_UINT64_TYPE) Long_val(pos), (void*) v,
       (ARCH_UINT64_TYPE) Wosize_val(v),
       descr);