diff --git a/Sources/backends/glsl.c b/Sources/backends/glsl.c
index 479f448..1b53243 100644
--- a/Sources/backends/glsl.c
+++ b/Sources/backends/glsl.c
@@ -76,7 +76,7 @@ static void write_code(char *glsl, char *directory, const char *filename, const
 
 		fprintf(file, "\";\n\n");
 
-		fprintf(file, "size_t %s_size = %" PRIu64 ";\n\n", name, length);
+		fprintf(file, "size_t %s_size = %zu;\n\n", name, length);
 
 		fprintf(file, "/*\n%s*/\n", glsl);
 
diff --git a/Sources/backends/hlsl.c b/Sources/backends/hlsl.c
index d930bca..3035e43 100644
--- a/Sources/backends/hlsl.c
+++ b/Sources/backends/hlsl.c
@@ -96,7 +96,7 @@ static void write_bytecode(char *hlsl, char *directory, const char *filename, co
 		}
 		fprintf(file, "\";\n");
 
-		fprintf(file, "size_t %s_size = %" PRIu64 ";\n\n", name, output_size);
+		fprintf(file, "size_t %s_size = %zu;\n\n", name, output_size);
 
 		fprintf(file, "/*\n%s*/\n", hlsl);
 
diff --git a/Sources/backends/wgsl.c b/Sources/backends/wgsl.c
index acfef5f..3a42885 100644
--- a/Sources/backends/wgsl.c
+++ b/Sources/backends/wgsl.c
@@ -81,7 +81,7 @@ static void write_code(char *wgsl, char *directory, const char *filename) {
 
 		fprintf(file, "\";\n\n");
 
-		fprintf(file, "size_t wgsl_size = %" PRIu64 ";\n\n", length);
+		fprintf(file, "size_t wgsl_size = %zu;\n\n", length);
 
 		fprintf(file, "/*\n%s*/\n", wgsl);