From 77ef89465665700103431bf0abcdb40deb1a37ba Mon Sep 17 00:00:00 2001
From: Alexander Medvednikov <alexander@medvednikov.com>
Date: Tue, 14 Apr 2026 12:45:34 +0300
Subject: [PATCH] cgen: C code compiling error (fixes #21939)

---
 vlib/v/gen/c/cheaders.v           |  6 ++----
 vlib/v/gen/c/noreturn_attr_test.v | 34 +++++++++++++++++++++++++++++++
 2 files changed, 36 insertions(+), 4 deletions(-)
 create mode 100644 vlib/v/gen/c/noreturn_attr_test.v

diff --git a/vlib/v/gen/c/cheaders.v b/vlib/v/gen/c/cheaders.v
index 0ce3e9902..1114e11de 100644
--- a/vlib/v/gen/c/cheaders.v
+++ b/vlib/v/gen/c/cheaders.v
@@ -262,10 +262,8 @@ const c_common_callconv_attr = '
 const c_common_noreturn_attr = '
 #if !defined(VNORETURN)
 	#if defined(__TINYC__)
-		#include <stdnoreturn.h>
-		#define VNORETURN noreturn
-	#endif
-	# if !defined(__TINYC__) && defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L
+		#define VNORETURN __attribute__((noreturn))
+	# elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L
 	#  define VNORETURN _Noreturn
 	# elif !defined(VNORETURN) && defined(__GNUC__) && __GNUC__ >= 2
 	#  define VNORETURN __attribute__((noreturn))
diff --git a/vlib/v/gen/c/noreturn_attr_test.v b/vlib/v/gen/c/noreturn_attr_test.v
new file mode 100644
index 000000000..d828221db
--- /dev/null
+++ b/vlib/v/gen/c/noreturn_attr_test.v
@@ -0,0 +1,34 @@
+import os
+
+const vexe = @VEXE
+
+const vroot = os.real_path(@VMODROOT)
+
+fn test_noreturn_attr_generation_does_not_depend_on_stdnoreturn_h() {
+	os.chdir(vroot) or {}
+	tmp_dir := os.join_path(os.vtmp_dir(), 'v_noreturn_attr_test')
+	os.mkdir_all(tmp_dir)!
+	defer {
+		os.rmdir_all(tmp_dir) or {}
+	}
+	source_path := os.join_path(tmp_dir, 'noreturn_attr_case.v')
+	source := [
+		'@[noreturn]',
+		'fn terminate() {',
+		'\texit(1)',
+		'}',
+		'',
+		'fn main() {',
+		'\tterminate()',
+		'}',
+	].join('\n')
+	os.write_file(source_path, source)!
+	cmd := '${os.quoted_path(vexe)} -o - ${os.quoted_path(source_path)}'
+	compilation := os.execute(cmd)
+	assert compilation.exit_code == 0
+	generated_c := compilation.output.replace('\r\n', '\n')
+	assert generated_c.contains('#if !defined(VNORETURN)')
+	assert generated_c.contains('#if defined(__TINYC__)')
+	assert generated_c.contains('#define VNORETURN __attribute__((noreturn))')
+	assert !generated_c.contains('#include <stdnoreturn.h>')
+}
-- 
2.39.5