diff --git a/auto/lib/openssl/conf b/auto/lib/openssl/conf
index 528ee17..a65815f 100644
--- a/auto/lib/openssl/conf
+++ b/auto/lib/openssl/conf
@@ -33,6 +33,10 @@
             CORE_LIBS="$CORE_LIBS $OPENSSL/.openssl/lib/libssl.a"
             CORE_LIBS="$CORE_LIBS $OPENSSL/.openssl/lib/libcrypto.a"
             CORE_LIBS="$CORE_LIBS $NGX_LIBDL"
+
+            if [ "$NGX_PLATFORM" = win32 ]; then
+                CORE_LIBS="$CORE_LIBS -lgdi32 -lcrypt32 -lws2_32"
+            fi
         ;;
     esac
 
diff --git a/auto/lib/pcre/conf b/auto/lib/pcre/conf
index 3458600..939f01b 100644
--- a/auto/lib/pcre/conf
+++ b/auto/lib/pcre/conf
@@ -73,6 +73,11 @@
 
         *)
             have=NGX_PCRE . auto/have
+
+            if [ "$NGX_PLATFORM" = win32 ]; then
+                have=PCRE_STATIC . auto/have
+            fi
+
             CORE_DEPS="$CORE_DEPS $PCRE/pcre.h"
             LINK_DEPS="$LINK_DEPS $PCRE/.libs/libpcre.a"
             CORE_LIBS="$CORE_LIBS $PCRE/.libs/libpcre.a"
diff --git a/auto/lib/pcre/make b/auto/lib/pcre/make
index c50d12f..0a27a11 100644
--- a/auto/lib/pcre/make
+++ b/auto/lib/pcre/make
@@ -23,14 +23,16 @@
         ngx_pcre=`echo \-DPCRE=\"$PCRE\" | sed -e "s/\//$ngx_regex_dirsep/g"`
     ;;
 
+    *)
+        ngx_makefile=
+    ;;
+
 esac
 
 
-case "$NGX_PLATFORM" in
+if [ -n "$ngx_makefile" ]; then
 
-    win32)
-
-        cat << END                                            >> $NGX_MAKEFILE
+    cat << END                                                >> $NGX_MAKEFILE
 
 `echo "$PCRE/pcre.lib:	$PCRE/pcre.h $NGX_MAKEFILE"			\
 	| sed -e "s/\//$ngx_regex_dirsep/g"`
@@ -41,10 +43,9 @@
 
 END
 
-    ;;
+else
 
-    *)
-        cat << END                                            >> $NGX_MAKEFILE
+    cat << END                                                >> $NGX_MAKEFILE
 
 $PCRE/pcre.h:	$PCRE/Makefile
 
@@ -60,6 +61,4 @@
 
 END
 
-    ;;
-
-esac
+fi
diff --git a/auto/lib/zlib/make b/auto/lib/zlib/make
index 9401a1d..7875ef6 100644
--- a/auto/lib/zlib/make
+++ b/auto/lib/zlib/make
@@ -24,6 +24,10 @@
         ngx_zlib=`echo \-DZLIB=\"$ZLIB\" | sed -e "s/\//$ngx_regex_dirsep/g"`
     ;;
 
+    *)
+        ngx_makefile=
+    ;;
+
 esac
 
 
@@ -33,13 +37,30 @@
 case "$NGX_PLATFORM" in
 
     win32)
-        cat << END                                            >> $NGX_MAKEFILE
+
+        if [ -n "$ngx_makefile" ]; then
+            cat << END                                        >> $NGX_MAKEFILE
 
 `echo "$ZLIB/zlib.lib:	$NGX_MAKEFILE" | sed -e "s/\//$ngx_regex_dirsep/g"`
 	\$(MAKE) -f auto/lib/zlib/$ngx_makefile $ngx_opt $ngx_zlib
 
 END
 
+        else
+
+            cat << END                                        >> $NGX_MAKEFILE
+
+$ZLIB/libz.a:	$NGX_MAKEFILE
+	cd $ZLIB \\
+	&& \$(MAKE) distclean \\
+	&& \$(MAKE) -f win32/Makefile.gcc \\
+		CFLAGS="$ZLIB_OPT" CC="\$(CC)" \\
+		libz.a
+
+END
+
+        fi
+
         done=YES
     ;;
 
diff --git a/auto/os/win32 b/auto/os/win32
index 21a54ba..0b9b461 100644
--- a/auto/os/win32
+++ b/auto/os/win32
@@ -9,10 +9,21 @@
 CORE_DEPS="$WIN32_DEPS"
 CORE_SRCS="$WIN32_SRCS $IOCP_SRCS"
 OS_CONFIG="$WIN32_CONFIG"
-CORE_LIBS="$CORE_LIBS advapi32.lib ws2_32.lib"
 NGX_ICONS="$NGX_WIN32_ICONS"
 SELECT_SRCS=$WIN32_SELECT_SRCS
 
+case "$NGX_CC_NAME" in
+
+    gcc)
+        CORE_LIBS="$CORE_LIBS -ladvapi32 -lws2_32"
+    ;;
+
+    *)
+        CORE_LIBS="$CORE_LIBS advapi32.lib ws2_32.lib"
+    ;;
+
+esac
+
 EVENT_MODULES="$EVENT_MODULES $IOCP_MODULE"
 EVENT_FOUND=YES
 
diff --git a/src/core/ngx_connection.c b/src/core/ngx_connection.c
index e12d3ef..28bf6ba 100644
--- a/src/core/ngx_connection.c
+++ b/src/core/ngx_connection.c
@@ -297,7 +297,7 @@
                 continue;
             }
 
-            if (ls[i].fd != -1) {
+            if (ls[i].fd != (ngx_socket_t) -1) {
                 continue;
             }
 
@@ -312,7 +312,7 @@
 
             s = ngx_socket(ls[i].sockaddr->sa_family, ls[i].type, 0);
 
-            if (s == -1) {
+            if (s == (ngx_socket_t) -1) {
                 ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno,
                               ngx_socket_n " %V failed", &ls[i].addr_text);
                 return NGX_ERROR;
@@ -863,7 +863,7 @@
     ngx_uint_t    log_error, level;
     ngx_socket_t  fd;
 
-    if (c->fd == -1) {
+    if (c->fd == (ngx_socket_t) -1) {
         ngx_log_error(NGX_LOG_ALERT, c->log, 0, "connection already closed");
         return;
     }
diff --git a/src/core/ngx_cycle.c b/src/core/ngx_cycle.c
index 2c006bc..eb39ab2 100644
--- a/src/core/ngx_cycle.c
+++ b/src/core/ngx_cycle.c
@@ -543,7 +543,7 @@
                 }
             }
 
-            if (nls[n].fd == -1) {
+            if (nls[n].fd == (ngx_socket_t) -1) {
                 nls[n].open = 1;
             }
         }
@@ -649,7 +649,7 @@
     ls = old_cycle->listening.elts;
     for (i = 0; i < old_cycle->listening.nelts; i++) {
 
-        if (ls[i].remain || ls[i].fd == -1) {
+        if (ls[i].remain || ls[i].fd == (ngx_socket_t) -1) {
             continue;
         }
 
@@ -813,7 +813,7 @@
 
     ls = cycle->listening.elts;
     for (i = 0; i < cycle->listening.nelts; i++) {
-        if (ls[i].fd == -1 || !ls[i].open) {
+        if (ls[i].fd == (ngx_socket_t) -1 || !ls[i].open) {
             continue;
         }
 
diff --git a/src/core/ngx_resolver.c b/src/core/ngx_resolver.c
index d59d0c4..d94477a 100644
--- a/src/core/ngx_resolver.c
+++ b/src/core/ngx_resolver.c
@@ -2221,7 +2221,7 @@
 
     ngx_log_debug1(NGX_LOG_DEBUG_EVENT, &uc->log, 0, "UDP socket %d", s);
 
-    if (s == -1) {
+    if (s == (ngx_socket_t) -1) {
         ngx_log_error(NGX_LOG_ALERT, &uc->log, ngx_socket_errno,
                       ngx_socket_n " failed");
         return NGX_ERROR;
diff --git a/src/event/modules/ngx_iocp_module.c b/src/event/modules/ngx_iocp_module.c
index bcaf71f..787e22d 100644
--- a/src/event/modules/ngx_iocp_module.c
+++ b/src/event/modules/ngx_iocp_module.c
@@ -170,7 +170,7 @@
 #endif
     }
 
-#ifdef __WATCOMC__
+#if defined(__WATCOMC__) || defined(__GNUC__)
     return 0;
 #endif
 }
diff --git a/src/event/modules/ngx_win32_select_module.c b/src/event/modules/ngx_win32_select_module.c
index 0a02ffc..eb5382d 100644
--- a/src/event/modules/ngx_win32_select_module.c
+++ b/src/event/modules/ngx_win32_select_module.c
@@ -148,8 +148,8 @@
         return NGX_ERROR;
     }
 
-    if ((event == NGX_READ_EVENT) && (max_read >= FD_SETSIZE)
-        || (event == NGX_WRITE_EVENT) && (max_write >= FD_SETSIZE))
+    if ((event == NGX_READ_EVENT && max_read >= FD_SETSIZE)
+        || (event == NGX_WRITE_EVENT && max_write >= FD_SETSIZE))
     {
         ngx_log_error(NGX_LOG_ERR, ev->log, 0,
                       "maximum number of descriptors "
diff --git a/src/event/ngx_event_accept.c b/src/event/ngx_event_accept.c
index 6f571f1..b114544 100644
--- a/src/event/ngx_event_accept.c
+++ b/src/event/ngx_event_accept.c
@@ -70,7 +70,7 @@
         s = accept(lc->fd, (struct sockaddr *) sa, &socklen);
 #endif
 
-        if (s == -1) {
+        if (s == (ngx_socket_t) -1) {
             err = ngx_socket_errno;
 
             if (err == NGX_EAGAIN) {
diff --git a/src/event/ngx_event_acceptex.c b/src/event/ngx_event_acceptex.c
index b7c4134..1fde031 100644
--- a/src/event/ngx_event_acceptex.c
+++ b/src/event/ngx_event_acceptex.c
@@ -108,7 +108,7 @@
         ngx_log_debug1(NGX_LOG_DEBUG_EVENT, &ls->log, 0,
                        ngx_socket_n " s:%d", s);
 
-        if (s == -1) {
+        if (s == (ngx_socket_t) -1) {
             ngx_log_error(NGX_LOG_ALERT, &ls->log, ngx_socket_errno,
                           ngx_socket_n " failed");
 
diff --git a/src/event/ngx_event_connect.c b/src/event/ngx_event_connect.c
index e6ae656..fddad0a 100644
--- a/src/event/ngx_event_connect.c
+++ b/src/event/ngx_event_connect.c
@@ -31,7 +31,7 @@
 
     ngx_log_debug1(NGX_LOG_DEBUG_EVENT, pc->log, 0, "socket %d", s);
 
-    if (s == -1) {
+    if (s == (ngx_socket_t) -1) {
         ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno,
                       ngx_socket_n " failed");
         return NGX_ERROR;
diff --git a/src/event/ngx_event_pipe.c b/src/event/ngx_event_pipe.c
index 4ef9b71..6f685a9 100644
--- a/src/event/ngx_event_pipe.c
+++ b/src/event/ngx_event_pipe.c
@@ -57,7 +57,7 @@
         do_write = 1;
     }
 
-    if (p->upstream->fd != -1) {
+    if (p->upstream->fd != (ngx_socket_t) -1) {
         rev = p->upstream->read;
 
         flags = (rev->eof || rev->error) ? NGX_CLOSE_EVENT : 0;
@@ -74,7 +74,9 @@
         }
     }
 
-    if (p->downstream->fd != -1 && p->downstream->data == p->output_ctx) {
+    if (p->downstream->fd != (ngx_socket_t) -1
+        && p->downstream->data == p->output_ctx)
+    {
         wev = p->downstream->write;
         if (ngx_handle_write_event(wev, p->send_lowat) != NGX_OK) {
             return NGX_ABORT;
diff --git a/src/os/win32/ngx_atomic.h b/src/os/win32/ngx_atomic.h
index 78d7424..d89a0d3 100644
--- a/src/os/win32/ngx_atomic.h
+++ b/src/os/win32/ngx_atomic.h
@@ -21,7 +21,8 @@
 #define NGX_ATOMIC_T_LEN            (sizeof("-2147483648") - 1)
 
 
-#if defined( __WATCOMC__ ) || defined( __BORLANDC__ ) || ( _MSC_VER >= 1300 )
+#if defined( __WATCOMC__ ) || defined( __BORLANDC__ ) || defined(__GNUC__)    \
+    || ( _MSC_VER >= 1300 )
 
 /* the new SDK headers */
 
diff --git a/src/os/win32/ngx_process_cycle.c b/src/os/win32/ngx_process_cycle.c
index 3a14aad..949ea85 100644
--- a/src/os/win32/ngx_process_cycle.c
+++ b/src/os/win32/ngx_process_cycle.c
@@ -815,7 +815,7 @@
 
                 /* THREAD: lock */
 
-                if (c[i].fd != -1 && c[i].idle) {
+                if (c[i].fd != (ngx_socket_t) -1 && c[i].idle) {
                     c[i].close = 1;
                     c[i].read->handler(c[i].read);
                 }
@@ -874,7 +874,7 @@
     if (ngx_exiting) {
         c = cycle->connections;
         for (i = 0; i < cycle->connection_n; i++) {
-            if (c[i].fd != -1
+            if (c[i].fd != (ngx_socket_t) -1
                 && c[i].read
                 && !c[i].read->accept
                 && !c[i].read->channel
diff --git a/src/os/win32/ngx_win32_config.h b/src/os/win32/ngx_win32_config.h
index 1930792..67105f1 100644
--- a/src/os/win32/ngx_win32_config.h
+++ b/src/os/win32/ngx_win32_config.h
@@ -9,6 +9,7 @@
 #define _NGX_WIN32_CONFIG_H_INCLUDED_
 
 
+#undef  WIN32
 #define WIN32         0x0400
 #define _WIN32_WINNT  0x0501
 
@@ -35,6 +36,12 @@
 #include <mswsock.h>
 #include <shellapi.h>
 #include <stddef.h>    /* offsetof() */
+
+#ifdef __GNUC__
+/* GCC MinGW's stdio.h includes sys/types.h */
+#define _OFF_T_
+#endif
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdarg.h>
diff --git a/src/os/win32/ngx_win32_init.c b/src/os/win32/ngx_win32_init.c
index cf73d82..d2505ce 100644
--- a/src/os/win32/ngx_win32_init.c
+++ b/src/os/win32/ngx_win32_init.c
@@ -141,7 +141,7 @@
      */
 
     s = ngx_socket(AF_INET, SOCK_STREAM, IPPROTO_IP);
-    if (s == -1) {
+    if (s == (ngx_socket_t) -1) {
         ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno,
                       ngx_socket_n " falied");
         return NGX_ERROR;
diff --git a/src/os/win32/ngx_wsarecv.c b/src/os/win32/ngx_wsarecv.c
index dd74ae2..1925f0b 100644
--- a/src/os/win32/ngx_wsarecv.c
+++ b/src/os/win32/ngx_wsarecv.c
@@ -17,7 +17,7 @@
     u_long        bytes, flags;
     WSABUF        wsabuf[1];
     ngx_err_t     err;
-    ngx_uint_t    n;
+    ngx_int_t     n;
     ngx_event_t  *rev;
 
     wsabuf[0].buf = (char *) buf;
@@ -70,7 +70,7 @@
     u_long            bytes, flags;
     WSABUF            wsabuf[1];
     ngx_err_t         err;
-    ngx_uint_t        n;
+    ngx_int_t         n;
     ngx_event_t      *rev;
     LPWSAOVERLAPPED   ovlp;