Win32: MinGW GCC compatibility.

Several warnings silenced, notably (ngx_socket_t) -1 is now checked
on socket operations instead of -1, as ngx_socket_t is unsigned on win32
and gcc complains on comparison.

With this patch, it's now possible to compile nginx using mingw gcc,
with options we normally compile on win32.

6 files changed, 10 insertions, 8 deletions

diff --git a/src/event/modules/ngx_iocp_module.c b/src/event/modules/ngx_iocp_module.c
index bcaf71f6d..787e22d80 100644
--- a/src/event/modules/ngx_iocp_module.c
+++ b/src/event/modules/ngx_iocp_module.c
@@ -170,7 +170,7 @@ ngx_iocp_timer(void *data)
 #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 0a02ffca0..eb5382d4e 100644
--- a/src/event/modules/ngx_win32_select_module.c
+++ b/src/event/modules/ngx_win32_select_module.c
@@ -148,8 +148,8 @@ ngx_select_add_event(ngx_event_t *ev, ngx_int_t event, ngx_uint_t flags)
         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 6f571f1a8..b1145446a 100644
--- a/src/event/ngx_event_accept.c
+++ b/src/event/ngx_event_accept.c
@@ -70,7 +70,7 @@ ngx_event_accept(ngx_event_t *ev)
         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 b7c4134b1..1fde03105 100644
--- a/src/event/ngx_event_acceptex.c
+++ b/src/event/ngx_event_acceptex.c
@@ -108,7 +108,7 @@ ngx_event_post_acceptex(ngx_listening_t *ls, ngx_uint_t n)
         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 e6ae6564e..fddad0a92 100644
--- a/src/event/ngx_event_connect.c
+++ b/src/event/ngx_event_connect.c
@@ -31,7 +31,7 @@ ngx_event_connect_peer(ngx_peer_connection_t *pc)
 
     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 4ef9b7103..6f685a9ed 100644
--- a/src/event/ngx_event_pipe.c
+++ b/src/event/ngx_event_pipe.c
@@ -57,7 +57,7 @@ ngx_event_pipe(ngx_event_pipe_t *p, ngx_int_t do_write)
         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 @@ ngx_event_pipe(ngx_event_pipe_t *p, ngx_int_t do_write)
         }
     }
 
-    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;