diff --git a/mongoose.c b/mongoose.c
index 584546a0..a5d1bcdb 100644
--- a/mongoose.c
+++ b/mongoose.c
@@ -3859,9 +3859,13 @@ struct mg_connection *mg_sntp_connect(struct mg_mgr *mgr, const char *url,
 #if MG_ENABLE_SOCKET
 #if MG_ARCH == MG_ARCH_WIN32 && MG_ENABLE_WINSOCK
 #define MG_SOCK_ERRNO WSAGetLastError()
+#if defined(_MSC_VER)
+#pragma comment(lib, "ws2_32.lib")
+#define alloca(a) _alloca(a)
+#endif
+#define poll(a, b, c) WSAPoll((a), (b), (c))
 #ifndef SO_EXCLUSIVEADDRUSE
 #define SO_EXCLUSIVEADDRUSE ((int) (~SO_REUSEADDR))
-#pragma comment(lib, "ws2_32.lib")
 #endif
 #elif MG_ARCH == MG_ARCH_FREERTOS_TCP
 #define MG_SOCK_ERRNO errno
@@ -4362,11 +4366,10 @@ static void mg_iotest(struct mg_mgr *mgr, int ms) {
                     eSELECT_READ | eSELECT_EXCEPT | eSELECT_WRITE);
   }
 #elif MG_ENABLE_POLL
-  nfds_t n = 0;
+  size_t n = 0;
   for (struct mg_connection *c = mgr->conns; c != NULL; c = c->next) n++;
-  struct pollfd fds[n == 0 ? 1 : n];  // Avoid zero-length VLA
-
-  memset(fds, 0, sizeof(fds));
+  struct pollfd *fds = (struct pollfd *) alloca(n * sizeof(fds[0]));
+  if (n > 0) memset(fds, 0, sizeof(n * sizeof(fds[0])));
   n = 0;
   for (struct mg_connection *c = mgr->conns; c != NULL; c = c->next) {
     c->is_readable = c->is_writable = 0;
diff --git a/src/sock.c b/src/sock.c
index 84b90bf2..a210fa98 100644
--- a/src/sock.c
+++ b/src/sock.c
@@ -11,9 +11,13 @@
 #if MG_ENABLE_SOCKET
 #if MG_ARCH == MG_ARCH_WIN32 && MG_ENABLE_WINSOCK
 #define MG_SOCK_ERRNO WSAGetLastError()
+#if defined(_MSC_VER)
+#pragma comment(lib, "ws2_32.lib")
+#define alloca(a) _alloca(a)
+#endif
+#define poll(a, b, c) WSAPoll((a), (b), (c))
 #ifndef SO_EXCLUSIVEADDRUSE
 #define SO_EXCLUSIVEADDRUSE ((int) (~SO_REUSEADDR))
-#pragma comment(lib, "ws2_32.lib")
 #endif
 #elif MG_ARCH == MG_ARCH_FREERTOS_TCP
 #define MG_SOCK_ERRNO errno
@@ -514,11 +518,10 @@ static void mg_iotest(struct mg_mgr *mgr, int ms) {
                     eSELECT_READ | eSELECT_EXCEPT | eSELECT_WRITE);
   }
 #elif MG_ENABLE_POLL
-  nfds_t n = 0;
+  size_t n = 0;
   for (struct mg_connection *c = mgr->conns; c != NULL; c = c->next) n++;
-  struct pollfd fds[n == 0 ? 1 : n];  // Avoid zero-length VLA
-
-  memset(fds, 0, sizeof(fds));
+  struct pollfd *fds = (struct pollfd *) alloca(n * sizeof(fds[0]));
+  if (n > 0) memset(fds, 0, sizeof(n * sizeof(fds[0])));
   n = 0;
   for (struct mg_connection *c = mgr->conns; c != NULL; c = c->next) {
     c->is_readable = c->is_writable = 0;