diff --git a/ext/prism/extension.c b/ext/prism/extension.c
index db9fe78f349..824f7ad04e6 100644
--- a/ext/prism/extension.c
+++ b/ext/prism/extension.c
@@ -613,8 +613,7 @@ parse_lex_file(VALUE self, VALUE filepath) {
  */
 static VALUE
 named_captures(VALUE self, VALUE source) {
-    pm_string_list_t string_list;
-    pm_string_list_init(&string_list);
+    pm_string_list_t string_list = { 0 };
 
     if (!pm_regexp_named_capture_group_names((const uint8_t *) RSTRING_PTR(source), RSTRING_LEN(source), &string_list, false, &pm_encoding_utf_8)) {
         pm_string_list_free(&string_list);
diff --git a/fuzz/regexp.c b/fuzz/regexp.c
index fd828f6e8f1..77a456dea6e 100644
--- a/fuzz/regexp.c
+++ b/fuzz/regexp.c
@@ -2,8 +2,7 @@
 
 void
 harness(const uint8_t *input, size_t size) {
-    pm_string_list_t capture_list;
-    pm_string_list_init(&capture_list);
+    pm_string_list_t capture_list = { 0 };
     pm_regexp_named_capture_group_names(input, size, &capture_list, false, &pm_encoding_utf_8);
     pm_string_list_free(&capture_list);
 }
diff --git a/include/prism/util/pm_string_list.h b/include/prism/util/pm_string_list.h
index 5aa37587758..1f460e5dc9c 100644
--- a/include/prism/util/pm_string_list.h
+++ b/include/prism/util/pm_string_list.h
@@ -21,13 +21,6 @@ typedef struct {
     pm_string_t *strings;
 } pm_string_list_t;
 
-/**
- * Initialize a pm_string_list_t with its default values.
- *
- * @param string_list The string list to initialize.
- */
-PRISM_EXPORTED_FUNCTION void pm_string_list_init(pm_string_list_t *string_list);
-
 /**
  * Append a pm_string_t to the given string list.
  *
diff --git a/src/prism.c b/src/prism.c
index 3422aa5894d..0a8c26ea185 100644
--- a/src/prism.c
+++ b/src/prism.c
@@ -14706,10 +14706,9 @@ parse_call_operator_write(pm_parser_t *parser, pm_call_node_t *call_node, const
 // match write node.
 static pm_node_t *
 parse_regular_expression_named_captures(pm_parser_t *parser, const pm_string_t *content, pm_call_node_t *call) {
-    pm_string_list_t named_captures;
-    pm_string_list_init(&named_captures);
-
+    pm_string_list_t named_captures = { 0 };
     pm_node_t *result;
+
     if (pm_regexp_named_capture_group_names(pm_string_source(content), pm_string_length(content), &named_captures, parser->encoding_changed, &parser->encoding) && (named_captures.length > 0)) {
         pm_match_write_node_t *match = pm_match_write_node_create(parser, call);
 
@@ -14718,14 +14717,12 @@ parse_regular_expression_named_captures(pm_parser_t *parser, const pm_string_t *
             pm_constant_id_t local;
 
             if (content->type == PM_STRING_SHARED) {
-                // If the unescaped string is a slice of the source,
-                // then we can copy the names directly. The pointers
-                // will line up.
+                // If the unescaped string is a slice of the source, then we can
+                // copy the names directly. The pointers will line up.
                 local = pm_parser_local_add_location(parser, name->source, name->source + name->length);
             } else {
-                // Otherwise, the name is a slice of the malloc-ed
-                // owned string, in which case we need to copy it
-                // out into a new string.
+                // Otherwise, the name is a slice of the malloc-ed owned string,
+                // in which case we need to copy it out into a new string.
                 size_t length = pm_string_length(name);
 
                 void *memory = malloc(length);
diff --git a/src/util/pm_string_list.c b/src/util/pm_string_list.c
index fa7f20619f1..d49e4ed734d 100644
--- a/src/util/pm_string_list.c
+++ b/src/util/pm_string_list.c
@@ -1,26 +1,19 @@
 #include "prism/util/pm_string_list.h"
 
-/**
- * Initialize a pm_string_list_t with its default values.
- */
-void
-pm_string_list_init(pm_string_list_t *string_list) {
-    string_list->length = 0;
-    string_list->capacity = 1;
-    string_list->strings = (pm_string_t *) malloc(sizeof(pm_string_t));
-}
-
 /**
  * Append a pm_string_t to the given string list.
  */
 void
 pm_string_list_append(pm_string_list_t *string_list, pm_string_t *string) {
     if (string_list->length + 1 > string_list->capacity) {
-        pm_string_t *original_string = string_list->strings;
-        string_list->capacity *= 2;
-        string_list->strings = (pm_string_t *) malloc(string_list->capacity * sizeof(pm_string_t));
-        memcpy(string_list->strings, original_string, (string_list->length) * sizeof(pm_string_t));
-        free(original_string);
+        if (string_list->capacity == 0) {
+            string_list->capacity = 1;
+        } else {
+            string_list->capacity *= 2;
+        }
+
+        string_list->strings = realloc(string_list->strings, string_list->capacity * sizeof(pm_string_t));
+        if (string_list->strings == NULL) abort();
     }
 
     string_list->strings[string_list->length++] = *string;