diff --git a/ext/mysqlnd/mysqlnd_alloc.c b/ext/mysqlnd/mysqlnd_alloc.c
index 12fa5fb723ae..187298ca9969 100644
--- a/ext/mysqlnd/mysqlnd_alloc.c
+++ b/ext/mysqlnd/mysqlnd_alloc.c
@@ -199,7 +199,7 @@ static void _mysqlnd_efree(void *ptr MYSQLND_MEM_D)
 
 #if PHP_DEBUG
 	{
-		char * fn = strrchr(__zend_filename, PHP_DIR_SEPARATOR);
+		const char * fn = strrchr(__zend_filename, PHP_DIR_SEPARATOR);
 		TRACE_ALLOC_INF_FMT("file=%-15s line=%4d", fn? fn + 1:__zend_filename, __zend_lineno);
 	}
 #endif
@@ -230,7 +230,7 @@ static void _mysqlnd_pefree(void *ptr, bool persistent MYSQLND_MEM_D)
 
 #if PHP_DEBUG
 	{
-		char * fn = strrchr(__zend_filename, PHP_DIR_SEPARATOR);
+		const char * fn = strrchr(__zend_filename, PHP_DIR_SEPARATOR);
 		TRACE_ALLOC_INF_FMT("file=%-15s line=%4d", fn? fn + 1:__zend_filename, __zend_lineno);
 	}
 #endif
@@ -262,7 +262,7 @@ static char * _mysqlnd_pememdup(const char * const ptr, size_t length, bool pers
 
 #if PHP_DEBUG
 	{
-		char * fn = strrchr(__zend_filename, PHP_DIR_SEPARATOR);
+		const char * fn = strrchr(__zend_filename, PHP_DIR_SEPARATOR);
 		TRACE_ALLOC_INF_FMT("file=%-15s line=%4d", fn? fn + 1:__zend_filename, __zend_lineno);
 	}
 #endif
@@ -293,7 +293,7 @@ static char * _mysqlnd_pestrndup(const char * const ptr, size_t length, bool per
 
 #if PHP_DEBUG
 	{
-		char * fn = strrchr(__zend_filename, PHP_DIR_SEPARATOR);
+		const char * fn = strrchr(__zend_filename, PHP_DIR_SEPARATOR);
 		TRACE_ALLOC_INF_FMT("file=%-15s line=%4d", fn? fn + 1:__zend_filename, __zend_lineno);
 	}
 #endif
@@ -334,7 +334,7 @@ static char * _mysqlnd_pestrdup(const char * const ptr, bool persistent MYSQLND_
 	TRACE_ALLOC_ENTER(mysqlnd_pestrdup_name);
 #if PHP_DEBUG
 	{
-		char * fn = strrchr(__zend_filename, PHP_DIR_SEPARATOR);
+		const char * fn = strrchr(__zend_filename, PHP_DIR_SEPARATOR);
 		TRACE_ALLOC_INF_FMT("file=%-15s line=%4d", fn? fn + 1:__zend_filename, __zend_lineno);
 	}
 #endif
diff --git a/ext/mysqlnd/mysqlnd_connection.c b/ext/mysqlnd/mysqlnd_connection.c
index c3a04388c65b..517b149c0b4d 100644
--- a/ext/mysqlnd/mysqlnd_connection.c
+++ b/ext/mysqlnd/mysqlnd_connection.c
@@ -550,7 +550,7 @@ MYSQLND_METHOD(mysqlnd_conn_data, get_scheme)(MYSQLND_CONN_DATA * conn, MYSQLND_
 			/* IPv6 without square brackets so without port */
 			transport.l = mnd_sprintf(&transport.s, 0, "tcp://[%s]:%u", hostname.s, port);
 		} else {
-			char *p;
+			const char *p;
 
 			/* IPv6 addresses are in the format [address]:port */
 			if (hostname.s[0] == '[') { /* IPv6 */
diff --git a/ext/mysqlnd/mysqlnd_result.c b/ext/mysqlnd/mysqlnd_result.c
index bce57b0ab052..1f811c8795df 100644
--- a/ext/mysqlnd/mysqlnd_result.c
+++ b/ext/mysqlnd/mysqlnd_result.c
@@ -990,7 +990,7 @@ MYSQLND_METHOD(mysqlnd_res, fetch_into)(MYSQLND_RES * result, const unsigned int
 
 	HashTable *row_ht = Z_ARRVAL_P(return_value);
 	MYSQLND_FIELD *field = meta->fields;
-	for (unsigned i = 0; i < meta->field_count; i++, field++) {
+	for (unsigned i = 0; i < meta->field_count; i++) {
 		zval *data = &row_data[i];
 
 		if (flags & MYSQLND_FETCH_NUM) {
@@ -1026,10 +1026,9 @@ MYSQLND_METHOD(mysqlnd_res, fetch_row_c)(MYSQLND_RES * result)
 	mysqlnd_result_free_prev_data(result);
 	if (result->m.fetch_row(result, &row_data, 0, &fetched_anything) == PASS && fetched_anything) {
 		unsigned field_count = result->field_count;
-		MYSQLND_FIELD *field = result->meta->fields;
 
 		ret = mnd_emalloc(field_count * sizeof(char *));
-		for (unsigned i = 0; i < field_count; i++, field++) {
+		for (unsigned i = 0; i < field_count; i++) {
 			zval *data = &row_data[i];
 			if (Z_TYPE_P(data) != IS_NULL) {
 				convert_to_string(data);
diff --git a/ext/mysqlnd/mysqlnd_wireprotocol.c b/ext/mysqlnd/mysqlnd_wireprotocol.c
index 633a4cca1623..b957240a4088 100644
--- a/ext/mysqlnd/mysqlnd_wireprotocol.c
+++ b/ext/mysqlnd/mysqlnd_wireprotocol.c
@@ -459,7 +459,7 @@ php_mysqlnd_greet_read(MYSQLND_CONN_DATA * conn, void * _packet)
 			packet->auth_protocol = estrdup("");
 		} else {
 			/* Check if NUL present */
-			char *null_terminator = memchr(p, '\0', remaining_size);
+			const char *null_terminator = memchr(p, '\0', remaining_size);
 			size_t auth_protocol_len;
 			if (null_terminator) {
 				/* If present, do basically estrdup */
diff --git a/ext/opcache/zend_persist.c b/ext/opcache/zend_persist.c
index 973e441edc80..c06452e6acf2 100644
--- a/ext/opcache/zend_persist.c
+++ b/ext/opcache/zend_persist.c
@@ -542,9 +542,8 @@ static void zend_persist_op_array_ex(zend_op_array *op_array, zend_persistent_sc
 		zend_op *new_opcodes = zend_shared_memdup_put(op_array->opcodes, sizeof(zend_op) * op_array->last);
 		zend_op *opline = new_opcodes;
 		zend_op *end = new_opcodes + op_array->last;
-		int offset = 0;
 
-		for (; opline < end ; opline++, offset++) {
+		for (; opline < end ; opline++) {
 #if ZEND_USE_ABS_CONST_ADDR
 			if (opline->op1_type == IS_CONST) {
 				opline->op1.zv = (zval*)((char*)opline->op1.zv + ((char*)op_array->literals - (char*)orig_literals));
diff --git a/ext/phar/phar_object.c b/ext/phar/phar_object.c
index 66d543732407..260214cc3687 100644
--- a/ext/phar/phar_object.c
+++ b/ext/phar/phar_object.c
@@ -349,9 +349,9 @@ static void phar_do_404(phar_archive_data *phar, char *fname, size_t fname_len,
 /* post-process REQUEST_URI and retrieve the actual request URI.  This is for
    cases like http://localhost/blah.phar/path/to/file.php/extra/stuff
    which calls "blah.phar" file "path/to/file.php" with PATH_INFO "/extra/stuff" */
-static void phar_postprocess_ru_web(const char *fname, size_t fname_len, const char *entry, size_t *entry_len, char **ru, size_t *ru_len) /* {{{ */
+static void phar_postprocess_ru_web(const char *fname, size_t fname_len, char *entry, size_t *entry_len, char **ru, size_t *ru_len) /* {{{ */
 {
-	const char *e = entry + 1;
+	char *e = entry + 1;
 	char *u1 = NULL, *u = NULL, *saveu = NULL;
 	size_t e_len = *entry_len - 1, u_len = 0;
 	phar_archive_data *pphar;