[Bug 53930] New: Build broken with Clang in MSVC mode due to OpenLDAP import using getopt.h

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=53930

Bug ID: 53930
           Summary: Build broken with Clang in MSVC mode due to OpenLDAP
                    import using getopt.h
           Product: Wine
           Version: unspecified
          Hardware: x86-64
                OS: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: wldap32
          Assignee: [e-mail]
          Reporter: [e-mail]
                CC: [e-mail], [e-mail],
                    [e-mail]
      Distribution: ---

Building with Clang in MSVC mode fails since the OpenLDAP code import. Building
fails with this error:

clang -c -o libs/ldap/aarch64-windows/liblber/io.o
../src/libs/ldap/liblber/io.c -Ilibs/ldap -I../src/libs/ldap -Iinclude \
  -I../src/include -I../src/include/msvcrt -I../src/libs/ldap/include
-D_TIMEVAL_DEFINED -D_UCRT \
  -D__WINE_PE_BUILD -target aarch64-windows -fno-strict-aliasing
-Wno-pragma-pack -Wno-format \
  -gdwarf-4 -g -O2
In file included from ../src/libs/ldap/liblber/io.c:41:
../src/libs/ldap/include/ac/unistd.h:44:11: fatal error: 'getopt.h' file not
found
#       include <getopt.h>
                ^~~~~~~~~~
1 error generated.
make: *** [Makefile:197943: libs/ldap/aarch64-windows/liblber/io.o] Error 1

The bundled libs/ldap/include/portable.h contains "#define HAVE_GETOPT_H 1".
For mingw-based PE builds, this succeeds by including getopt.h from the mingw
toolchain (which probably isn't intended?), while if building with Clang in
MSVC mode, no such header is available.

(Side note: When building with a mingw compiler like this, it would probably be
good to avoid having the mingw sysroot includes available, to avoid
accidentally using headers from there. But one can't just use -nostdinc, since
that also excludes paths like the compiler's own headers, like stdarg.h.
Something like --sysroot=dummy might work.)