diff --git a/arch/x86/boot/tools/build.c b/arch/x86/boot/tools/build.c
index 94c5446..c941d6a 100644
--- a/arch/x86/boot/tools/build.c
+++ b/arch/x86/boot/tools/build.c
@@ -243,6 +243,7 @@
 	c = fread(buf, 1, sizeof(buf) - 1, file);
 	if (ferror(file))
 		die("read-error on `zoffset.h'");
+	fclose(file);
 	buf[c] = 0;
 
 	p = (char *)buf;