shut up valgrind

diff --git a/phpdbg_prompt.c b/phpdbg_prompt.c
index 056db99c1ccb4f5444666e2e083636ecbd0ec576..2deb3787982f5fa385c582acfb7dfdfec94d83dd 100644 (file)
--- a/phpdbg_prompt.c
+++ b/phpdbg_prompt.c
@@ -93,7 +93,7 @@ void phpdbg_init(char *init_file, size_t init_file_len, zend_bool use_default TS
                        while (fgets(cmd, PHPDBG_MAX_CMD, fp) != NULL) {
                                cmd_len = strlen(cmd)-1;
 
-                               while (cmd && isspace(cmd[cmd_len-1]))
+                               while (cmd && cmd_len > 0L && isspace(cmd[cmd_len-1]))
                                        cmd_len--;
 
                                cmd[cmd_len] = '\0';