From 1d66cc94509dbff0172c41e4310921c5c88655b1 Mon Sep 17 00:00:00 2001
From: Kai Ninomiya <kainino@chromium.org>
Date: Mon, 9 Dec 2024 16:18:21 -0500
Subject: [PATCH] Use 0.0f/0.0f instead of math.h NAN

IEEE754-2008 says it produces a quiet NaN, so as long as the system has
IEEE754 math this is fine.

The only reason to do this is to avoid including math.h.

Issue: 427
---
 gen/cheader.tmpl | 1 -
 gen/gen.go       | 2 +-
 webgpu.h         | 3 +--
 3 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/gen/cheader.tmpl b/gen/cheader.tmpl
index d491c67e..bdd32edc 100644
--- a/gen/cheader.tmpl
+++ b/gen/cheader.tmpl
@@ -67,7 +67,6 @@
 {{- if eq .Name "webgpu"}}
 #include <stdint.h>
 #include <stddef.h>
-#include <math.h>
 {{else}}
 #include "webgpu.h"
 {{end}}
diff --git a/gen/gen.go b/gen/gen.go
index 277221a7..3b6f87c1 100644
--- a/gen/gen.go
+++ b/gen/gen.go
@@ -196,7 +196,7 @@ func (g *Generator) CValue(s string) (string, error) {
 	case "uint64_max":
 		return "UINT64_MAX", nil
 	case "nan":
-		return "NAN", nil
+		return "0.0f / 0.0f", nil
 	default:
 		var num string
 		var base int
diff --git a/webgpu.h b/webgpu.h
index 6107babe..9a3bdab9 100644
--- a/webgpu.h
+++ b/webgpu.h
@@ -60,7 +60,6 @@
 
 #include <stdint.h>
 #include <stddef.h>
-#include <math.h>
 
 #define _wgpu_COMMA ,
 #if defined(__cplusplus)
@@ -92,7 +91,7 @@
  * Value to be assigned to member depthClearValue of @ref WGPURenderPassDepthStencilAttachment
  * to mean that it is not defined.
  */
-#define WGPU_DEPTH_CLEAR_VALUE_UNDEFINED (NAN)
+#define WGPU_DEPTH_CLEAR_VALUE_UNDEFINED (0.0f / 0.0f)
 #define WGPU_DEPTH_SLICE_UNDEFINED (UINT32_MAX)
 #define WGPU_LIMIT_U32_UNDEFINED (UINT32_MAX)
 #define WGPU_LIMIT_U64_UNDEFINED (UINT64_MAX)