configure: infer static linking of libwinpthread for MinGW

Merge to v6.3

racket/src/configure

@@ -4674,6 +4674,52 @@ $as_echo "#define HAVE_STDINT_H 1" >>confdefs.h
     if `which ${host}-dlltool > /dev/null` ; then
       DLLTOOL="${host}-dlltool"
     fi
+
+    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for pthread_create in -lwinpthread" >&5
+$as_echo_n "checking for pthread_create in -lwinpthread... " >&6; }
+if ${ac_cv_lib_winpthread_pthread_create+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_check_lib_save_LIBS=$LIBS
+LIBS="-lwinpthread  $LIBS"
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char pthread_create ();
+int
+main ()
+{
+return pthread_create ();
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  ac_cv_lib_winpthread_pthread_create=yes
+else
+  ac_cv_lib_winpthread_pthread_create=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_winpthread_pthread_create" >&5
+$as_echo "$ac_cv_lib_winpthread_pthread_create" >&6; }
+if test "x$ac_cv_lib_winpthread_pthread_create" = xyes; then :
+  has_winpthread=yes
+else
+  has_winpthread=no
+fi
+
+    if test "${has_winpthread}" == "yes" ; then
+      LIBS="${LIBS} -Wl,-Bstatic -lwinpthread"
+    fi
     case "$build_os" in
       *cygwin*)
         PWD="cygpath -m \\\`pwd\\\`"

racket/src/racket/configure.ac

@@ -796,6 +796,11 @@ case "$host_os" in
     if `which ${host}-dlltool > /dev/null` ; then
       DLLTOOL="${host}-dlltool"
     fi
+
+    AC_CHECK_LIB(winpthread, pthread_create, has_winpthread=yes, has_winpthread=no)
+    if test "${has_winpthread}" == "yes" ; then
+      LIBS="${LIBS} -Wl,-Bstatic -lwinpthread"
+    fi
     case "$build_os" in
       *cygwin*)
         PWD="cygpath -m \\\`pwd\\\`"