From 1a393bdffd9491939c4c15bee7a804b6bea2c7f3 Mon Sep 17 00:00:00 2001
From: Marco Roth <marco.roth@intergga.ch>
Date: Thu, 6 Nov 2025 22:12:51 +0100
Subject: [PATCH] C: Make `hb_buffer_append_char` thread-safe

---
 rust/Makefile        | 2 +-
 src/util/hb_buffer.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/rust/Makefile b/rust/Makefile
index a0ae1e4f3..83f6802ef 100644
--- a/rust/Makefile
+++ b/rust/Makefile
@@ -26,7 +26,7 @@ cli: build
 	@./bin/$(BIN_NAME) || true
 
 test: build
-	NO_COLOR=1 cargo +stable test --verbose -- --test-threads=1
+	NO_COLOR=1 cargo +stable test --verbose
 
 format:
 	cargo +nightly fmt
diff --git a/src/util/hb_buffer.c b/src/util/hb_buffer.c
index 34eae2c91..f6fd84152 100644
--- a/src/util/hb_buffer.c
+++ b/src/util/hb_buffer.c
@@ -142,7 +142,7 @@ void hb_buffer_append_string(hb_buffer_T* buffer, hb_string_T string) {
 }
 
 void hb_buffer_append_char(hb_buffer_T* buffer, const char character) {
-  static char string[2];
+  char string[2];
 
   string[0] = character;
   string[1] = '\0';