diff --git a/buffer.c b/buffer.c
index d85466d..1aa0340 100644
--- a/buffer.c
+++ b/buffer.c
@@ -56,9 +56,8 @@ buffer_t *buffer_new(void) {
 // Wrapper for buffer_new + buffer_open
 buffer_t *buffer_new_open(char *path) {
     buffer_t *self;
-    int rc;
     self = buffer_new();
-    if ((rc = buffer_open(self, path)) != MLBUF_OK) {
+    if (buffer_open(self, path) != MLBUF_OK) {
         buffer_destroy(self);
         return NULL;
     }
@@ -702,7 +701,8 @@ int buffer_get_bline_w_hint(buffer_t *self, bint_t line_index, bline_t *opt_hint
     MLBUF_MAKE_GT_EQ0(line_index);
 
     if (!opt_hint) {
-        opt_hint = self->first_line;
+        *ret_bline = NULL;
+        return MLBUF_ERR;
     }
 
     fwd = opt_hint;
@@ -1407,6 +1407,11 @@ static int _buffer_redo(buffer_t *self, int by_group) {
         // Get line to perform undo on
         bline = NULL;
         buffer_get_bline(self, action_to_redo->start_line_index, &bline);
+
+        if (!bline){
+            return MLBUF_ERR;
+        }
+
         MLBUF_BLINE_ENSURE_CHARS(bline);
         if (!bline) {
             return MLBUF_ERR;
@@ -1481,7 +1486,6 @@ static int _buffer_apply_styles_all(bline_t *bline, bint_t min_nlines) {
     open_rule = bline->prev ? bline->prev->eol_rule : NULL;
     styled_nlines = 0;
     col = 0;
-    eol_rule_changed = 0;
 
     _buffer_bline_reset_styles(bline);
 
diff --git a/cmd.c b/cmd.c
index 6382778..1076421 100644
--- a/cmd.c
+++ b/cmd.c
@@ -520,8 +520,8 @@ int cmd_replace_all(cmd_context_t *ctx) {
     cancelled = 0;
     regex = NULL;
     replacement = NULL;
-    num_bviews = 0;
     CDL_COUNT2(ctx->editor->all_bviews, bview, num_bviews, all_next);
+    if (num_bviews <= 0) return MLBUF_ERR;
     buffer_done = calloc(num_bviews, sizeof(buffer_t *));
     buffer_done_i = 0;
 
@@ -1619,7 +1619,6 @@ static int _cmd_save(editor_t *editor, bview_t *bview, int save_as) {
     struct stat st;
     bint_t nbytes;
 
-    fname_changed = 0;
     do {
         if (!bview->buffer->path || save_as) {
             // Prompt for name
@@ -1900,8 +1899,8 @@ static int _cmd_menu_ctag_cb(cmd_context_t *ctx) {
     }
     re += 2; // Skip leading `/^`
     re_len -= 2;
-    re[re_len-4] = '\0'; // Trunc trailing `$/;"`
     re_len -= 4;
+    re[re_len] = '\0'; // Trunc trailing `$/;"`
     util_pcre_replace("([\\.\\\\\\+\\*\\?\\^\\$\\[\\]\\(\\)\\{\\}\\=\\!\\>\\<\\|\\:\\-])", re, "\\\\$1", &qre, &qre_len);
     editor_close_bview(ctx->editor, ctx->bview, NULL);
     editor_open_bview(ctx->editor, NULL, MLE_BVIEW_TYPE_EDIT, fname, strlen(fname), 1, 0, 0, NULL, &bview);
diff --git a/editor.c b/editor.c
index 50670b1..c6b15d0 100644
--- a/editor.c
+++ b/editor.c
@@ -647,7 +647,9 @@ static int _editor_close_bview_inner(editor_t *editor, bview_t *bview, int *optr
     if (!bview->split_parent) {
         DL_DELETE2(editor->top_bviews, bview, top_prev, top_next);
     }
-    CDL_DELETE2(editor->all_bviews, bview, all_prev, all_next);
+    if (bview->all_next && bview->all_prev) {
+        CDL_DELETE2(editor->all_bviews, bview, all_prev, all_next);
+    }
     bview_destroy(bview);
     if (optret_num_closed) *optret_num_closed += 1;
     return MLE_OK;
@@ -1514,8 +1516,14 @@ static kbinding_t *_editor_get_kbinding_node(kbinding_t *node, kinput_t *input,
         }
     }
 
+    
     // Look for input
+    if (!node){
+        return NULL;
+    }
+
     HASH_FIND(hh, node->children, input, sizeof(kinput_t), binding);
+
     if (binding) {
         return binding;
     }
@@ -2268,7 +2276,13 @@ static void _editor_init_syntax_add_rule(syntax_t *syntax, srule_def_t *def) {
     } else {
         node->srule = srule_new_single(def->re, strlen(def->re), 0, def->fg, def->bg);
     }
-    if (node->srule) DL_APPEND(syntax->srules, node);
+
+    if (node->srule){ 
+        DL_APPEND(syntax->srules, node);
+        return;
+    }
+
+    free(node);
 }
 
 // Proxy for _editor_init_syntax_add_rule with str in format '<start>,<end>,<fg>,<bg>' or '<regex>,<fg>,<bg>'
diff --git a/util.c b/util.c
index 6573b64..36b9e3d 100644
--- a/util.c
+++ b/util.c
@@ -275,7 +275,6 @@ int util_pcre_replace(char *re, char *subj, char *repl, char **ret_result, int *
     num_repls = 0;
     subj_len = strlen(subj);
     subj_offset = 0;
-    subj_offset_z = 0;
     subj_look_offset = 0;
     last_look_offset = 0;
     while (subj_offset < subj_len) {
@@ -533,9 +532,9 @@ void str_sprintf(str_t *str, const char *fmt, ...) {
 void str_put_len(str_t *str, char *data, size_t data_len, int is_prepend) {
     size_t req_cap;
     req_cap = str->len + data_len + 1;
-    if (req_cap > str->cap) {
-        str_ensure_cap(str, req_cap);
-    }
+
+    str_ensure_cap(str, req_cap);
+
     if (is_prepend) {
         memmove(str->data + data_len, str->data, str->len);
         memcpy(str->data, data, data_len);
@@ -548,7 +547,7 @@ void str_put_len(str_t *str, char *data, size_t data_len, int is_prepend) {
 
 // Ensure space in str
 void str_ensure_cap(str_t *str, size_t cap) {
-    if (cap > str->cap) {
+    if (!str->data || cap > str->cap) {
         if (str->inc >= 0) {
             // If inc is positive, grow linearly
             cap = MLBUF_MAX(cap, str->cap + (str->inc > 0 ? str->inc : 128));