diff --git a/lib/ftp.c b/lib/ftp.c
index 5008d920e..9fe31b857 100644
--- a/lib/ftp.c
+++ b/lib/ftp.c
@@ -999,7 +999,6 @@ CURLcode ftp_use_port(struct connectdata *conn)
 #endif
   unsigned char *ap;
   unsigned char *pp;
-  int alen, plen;
   char portmsgbuf[4096], tmp[4096];
 
   const char *mode[] = { "EPRT", "LPRT", "PORT", NULL };
@@ -1062,6 +1061,7 @@ CURLcode ftp_use_port(struct connectdata *conn)
 
   for (modep = (char **)mode; modep && *modep; modep++) {
     int lprtaf, eprtaf;
+    int alen=0, plen=0;
     
     switch (sa->sa_family) {
     case AF_INET:
@@ -1363,7 +1363,7 @@ CURLcode ftp_use_pasv(struct connectdata *conn,
 #endif
   int modeoff;
   unsigned short connectport; /* the local port connect() should use! */
-  unsigned short newport; /* remote port, not necessary the local one */
+  unsigned short newport=0; /* remote port, not necessary the local one */
   
   /* newhost must be able to hold a full IP-style address in ASCII, which
      in the IPv6 case means 5*8-1 = 39 letters */
diff --git a/lib/getinfo.c b/lib/getinfo.c
index f2efbbaa6..01d6dda85 100644
--- a/lib/getinfo.c
+++ b/lib/getinfo.c
@@ -72,9 +72,9 @@ CURLcode Curl_initinfo(struct SessionHandle *data)
 CURLcode Curl_getinfo(struct SessionHandle *data, CURLINFO info, ...)
 {
   va_list arg;
-  long *param_longp;
-  double *param_doublep;
-  char **param_charp;
+  long *param_longp=NULL;
+  double *param_doublep=NULL;
+  char **param_charp=NULL;
   va_start(arg, info);
 
   switch(info&CURLINFO_TYPEMASK) {
diff --git a/lib/memdebug.h b/lib/memdebug.h
index b2399a269..3fa87ac9e 100644
--- a/lib/memdebug.h
+++ b/lib/memdebug.h
@@ -57,6 +57,7 @@ FILE *curl_fopen(const char *file, const char *mode, int line,
 int curl_fclose(FILE *file, int line, const char *source);
 
 /* Set this symbol on the command-line, recompile all lib-sources */
+#undef strdup
 #define strdup(ptr) curl_dostrdup(ptr, __LINE__, __FILE__)
 #define malloc(size) curl_domalloc(size, __LINE__, __FILE__)
 #define realloc(ptr,size) curl_dorealloc(ptr, size, __LINE__, __FILE__)
diff --git a/lib/url.c b/lib/url.c
index eb4003b22..edd2b3a39 100644
--- a/lib/url.c
+++ b/lib/url.c
@@ -1691,13 +1691,13 @@ static CURLcode CreateConnection(struct SessionHandle *data,
   int urllen;
   Curl_addrinfo *hostaddr;
 #ifdef HAVE_ALARM
-  unsigned int prev_alarm;
+  unsigned int prev_alarm=0;
 #endif
   char endbracket;
 
 #ifdef HAVE_SIGACTION
   struct sigaction keep_sigact;   /* store the old struct here */
-  bool keep_copysig;              /* did copy it? */
+  bool keep_copysig=FALSE;        /* did copy it? */
 #else
 #ifdef HAVE_SIGNAL
   void *keep_sigact;              /* store the old handler here */