diff --git a/src/http.c b/src/http.c
index 3f2744e..1f87209 100644
--- a/src/http.c
+++ b/src/http.c
@@ -39,6 +39,12 @@ CMUTIL_LogDefine("cmutils.http")
 // absurd or hostile length headers.
 #define CMUTIL_HTTP_MAX_BODY    (1024L*1024L*1024L)
 
+// How wide a host name this client stores, and how wide the "host:port"
+// key derived from it can get - a truncated key would let two different
+// hosts share one connection pool.
+#define CMUTIL_HTTP_HOST_MAX    256
+#define CMUTIL_HTTP_POOLKEY_MAX (CMUTIL_HTTP_HOST_MAX + 16)
+
 struct CMUTIL_HttpContext {
     CMUTIL_Map      *socket_pools;
     CMUTIL_Mutex    *socket_pools_mutex;
@@ -48,7 +54,7 @@ struct CMUTIL_HttpContext {
 typedef struct CMUTIL_SocketPoolElem {
     time_t          last_used;
     CMUTIL_Mem      *memst;
-    char            host[256];
+    char            host[CMUTIL_HTTP_HOST_MAX];
     int             port;
     CMUTIL_Socket   *sock;
 } CMUTIL_SocketPoolElem;
@@ -120,7 +126,7 @@ CMUTIL_STATIC CMUTIL_Socket *CMUTIL_HttpContextGetSocket(
 {
     CMUTIL_Pool *pool = NULL;
     CMUTIL_SocketPoolElem *elem = NULL;
-    char buf[256];
+    char buf[CMUTIL_HTTP_POOLKEY_MAX];
     snprintf(buf, sizeof(buf), "%s:%d", host, port);
     CMCall(g_httpctx.socket_pools_mutex, Lock);
     pool = CMCall(g_httpctx.socket_pools, Get, buf);
@@ -164,7 +170,7 @@ CMUTIL_STATIC CMBool CMUTIL_HttpContextPutSocket(
     const char *host, int port, CMUTIL_Socket *sock)
 {
     CMUTIL_Pool *pool = NULL;
-    char buf[256];
+    char buf[CMUTIL_HTTP_POOLKEY_MAX];
     CMBool res = CMFalse;
     snprintf(buf, sizeof(buf), "%s:%d", host, port);
     CMCall(g_httpctx.socket_pools_mutex, Lock);
@@ -192,7 +198,7 @@ CMUTIL_STATIC CMBool CMUTIL_HttpContextPutSocket(
 typedef struct CMUTIL_HttpClient_Internal {
     CMUTIL_HttpClient   base;
     CMUTIL_Mem          *memst;
-    char                host[256];
+    char                host[CMUTIL_HTTP_HOST_MAX];
     int                 port;
     CMBool              ishttps;
     CMBool              verifypeer;
@@ -329,7 +335,7 @@ CMUTIL_STATIC CMSocketResult CMUTIL_HttpClientWriteLine(
 {
     CMSocketResult sr = CMSocketOk;
     if (line && *line)
-        sr = CMCall(sock, Write, line, strlen(line), timeout);
+        sr = CMCall(sock, Write, line, (uint32_t)strlen(line), timeout);
     if (sr == CMSocketOk)
         sr = CMCall(sock, Write, "\r\n", 2, timeout);
     CMLogTrace("Write -> %s", line);
@@ -438,7 +444,7 @@ CMUTIL_STATIC CMUTIL_ByteBuffer *CMUTIL_HttpClientRequest(
             // Content-Length already delimits the body. A CRLF after it is
             // extra bytes the peer reads as the start of the next request,
             // which desynchronizes a kept-alive connection.
-            sr = CMCall(sock, Write, data, size, timeout);
+            sr = CMCall(sock, Write, data, (uint32_t)size, timeout);
             if (sr != CMSocketOk) {
                 CMLogError("failed to write request body");
                 goto FAILED;
diff --git a/src/network.c b/src/network.c
index ced2a6b..4ab9979 100644
--- a/src/network.c
+++ b/src/network.c
@@ -406,10 +406,12 @@ CMSocketResult CMUTIL_SocketCheckBase(
     tv.tv_sec = timeout / 1000;
     tv.tv_usec = (int)((timeout % 1000) * 1000);
 
+    // nfds is an int; a SOCKET is a 64 bit handle on Windows, where the
+    // argument is ignored outright.
     if (isread) {
-        rc = select(sock+1, &fdset, NULL, NULL, &tv);
+        rc = select((int)(sock+1), &fdset, NULL, NULL, &tv);
     } else {
-        rc = select(sock+1, NULL, &fdset, NULL, &tv);
+        rc = select((int)(sock+1), NULL, &fdset, NULL, &tv);
     }
     if (rc < 0) {
         if (!silent)
@@ -837,7 +839,7 @@ CMUTIL_STATIC CMBool CMUTIL_SocketConnectByIP(
         return CMFalse;
     }
 
-    rc = connect(s, (struct sockaddr*)addr, addrlen);
+    rc = connect(s, (struct sockaddr*)addr, (socklen_t)addrlen);
     is->sock = s;
     if (rc < 0) {
 
@@ -1128,9 +1130,9 @@ CMUTIL_STATIC CMBool CMUTIL_SocketConnectIPCInternal(
 {
     struct sockaddr_storage ss;
 #if defined(MSWIN)
-    struct sockaddr_in *sin = (struct sockaddr_in*)&ss;
-    long port = strtol(ipc_path, NULL, 10);
-    CMUTIL_SocketAddrSet(sin, "127.0.0.1", port);
+    // IPC is a loopback connection here, with the path naming the port.
+    const long port = strtol(ipc_path, NULL, 10);
+    CMUTIL_SocketAddrSet(&ss, "127.0.0.1", (int)port);
 #else
     struct sockaddr_un *sun = (struct sockaddr_un*)&ss;
     if (strlen(ipc_path) >= sizeof(sun->sun_path) - 1) {
@@ -1394,7 +1396,7 @@ CMUTIL_STATIC CMBool CMUTIL_ServerSocketCreateBase(
         goto FAILED;
     }
 
-    rc = bind(sock, (struct sockaddr *) &addr, addrlen);
+    rc = bind(sock, (struct sockaddr *) &addr, (socklen_t)addrlen);
     if (rc == SOCKET_ERROR) {
         if (res->silent)
             CMLogTrace("bind failed.(%d:%s)", errno, strerror(errno));
diff --git a/test/crypto_test.c b/test/crypto_test.c
index 4de3677..b90532b 100644
--- a/test/crypto_test.c
+++ b/test/crypto_test.c
@@ -81,8 +81,6 @@ int main() {
     OpenSSL_add_all_algorithms();
     CMUTIL_Init(CMUTIL_MEM_TYPE);
 
-    EVP_CIPHER *cipher;
-
     CMUTIL_BlockCrypto *block = NULL;
     CMUTIL_Map *env = NULL;
     CMUTIL_String *pathstr = NULL;
@@ -198,7 +196,8 @@ int main() {
         "6wIDAQAB\n"
         "-----END PUBLIC KEY-----";
 
-    priv = CMUTIL_PrivateKeyCreateFromPEM(priv_pem, "");
+    /* the passphrase is bytes, not text */
+    priv = CMUTIL_PrivateKeyCreateFromPEM(priv_pem, (const uint8_t*)"");
     ASSERT(priv != NULL, "CMUTIL_PrivateKeyCreateFromPEM");
 
     pub = CMUTIL_PublicKeyCreateFromPEM(pub_pem);
diff --git a/test/dgram_test.c b/test/dgram_test.c
index 61a918a..af28b0a 100644
--- a/test/dgram_test.c
+++ b/test/dgram_test.c
@@ -92,7 +92,7 @@ int main() {
     CMLogInfo("datagram socket connected to %s:%d", rhost, rport);
 
     const char *send_data = "this is sample message";
-    CMCall(buffer, AddBytes, (const uint8_t*)send_data, strlen(send_data));
+    CMCall(buffer, AddBytes, (const uint8_t*)send_data, (uint32_t)strlen(send_data));
     sr = CMCall(client, Send, buffer, 1000);
     ASSERT(sr == CMSocketOk, "Send");
 
@@ -108,7 +108,7 @@ int main() {
 
     client = CMUTIL_DGramSocketCreateBind(NULL);
     send_data = "second data";
-    CMCall(buffer, AddBytes, (const uint8_t*)send_data, strlen(send_data));
+    CMCall(buffer, AddBytes, (const uint8_t*)send_data, (uint32_t)strlen(send_data));
     sr = CMCall(client, SendTo, buffer, &localaddr, 1000);
     ASSERT(sr == CMSocketOk, "SendTo");
 
@@ -127,7 +127,7 @@ int main() {
 
     CMCall(buffer, Clear);
     send_data = "!@#$$#@!";
-    CMCall(buffer, AddBytes, (const uint8_t*)send_data, strlen(send_data));
+    CMCall(buffer, AddBytes, (const uint8_t*)send_data, (uint32_t)strlen(send_data));
     sr = CMCall(client, SendTo, buffer, &localaddr, 1000);
     if (sr != CMSocketOk) {
         CMLogError("datagram socket send failed - failed");
diff --git a/test/network_test.c b/test/network_test.c
index c721b53..75fc5ef 100644
--- a/test/network_test.c
+++ b/test/network_test.c
@@ -38,7 +38,7 @@ void client_handler(void* udata) {
             CMCall(str, InsertPrint, 0, "%04d", len);
             p = (uint8_t*)CMCall(str, GetCString);
             blen = CMCall(str, GetSize);
-            sr = CMCall(csock, Write, p, blen, 1000);
+            sr = CMCall(csock, Write, p, (uint32_t)blen, 1000);
             if (sr != CMSocketOk) break;
             CMLogInfo("sent to client: %s", CMCall(str, GetCString));
             CMCall(buf, Clear);
@@ -93,11 +93,11 @@ void client_proc(void* udata) {
         CMLogInfo("connected to server: %s:%d", host, port);
         for (int i=0; i<10; i++) {
             CMCall(sbuf, AddPrint, "%s: %d", tname, i);
-            int len = CMCall(sbuf, GetSize);
+            int len = (int)CMCall(sbuf, GetSize);
             CMCall(sbuf, InsertPrint, 0, "%04d", len);
             uint8_t *p = (uint8_t*)CMCall(sbuf, GetCString);
             size_t blen = CMCall(sbuf, GetSize);
-            sr = CMCall(csock, Write, p, blen, 1000);
+            sr = CMCall(csock, Write, p, (uint32_t)blen, 1000);
             if (sr != CMSocketOk) break;
             CMLogInfo("sent to server: %s", CMCall(sbuf, GetCString));
             CMCall(sbuf, Clear);