From d90f2ba1faa0a68f3d3d0c9f1b34e447f8e41287 Mon Sep 17 00:00:00 2001
From: Christoph Oelckers <coelckers@users.noreply.github.com>
Date: Sun, 5 Feb 2017 21:54:09 +0100
Subject: [PATCH] - wrap the va_list that gets passed around by the Draw
 functions into a struct so that the templates can use reliable, identical
 semantics for both this and the VM's arg list.

---
 src/v_draw.cpp | 28 ++++++++++++++--------------
 src/v_text.cpp | 12 ++++++------
 src/v_video.h  |  5 +++++
 3 files changed, 25 insertions(+), 20 deletions(-)

diff --git a/src/v_draw.cpp b/src/v_draw.cpp
index 52f8cde7a..6f0e8330a 100644
--- a/src/v_draw.cpp
+++ b/src/v_draw.cpp
@@ -129,12 +129,12 @@ static int PalFromRGB(uint32 rgb)
 
 void DCanvas::DrawTexture (FTexture *img, double x, double y, int tags_first, ...)
 {
-	va_list tags;
-	va_start(tags, tags_first);
+	Va_List tags;
+	va_start(tags.list, tags_first);
 	DrawParms parms;
 
 	bool res = ParseDrawTextureTags(img, x, y, tags_first, tags, &parms, false);
-	va_end(tags);
+	va_end(tags.list);
 	if (!res)
 	{
 		return;
@@ -457,30 +457,30 @@ bool DCanvas::SetTextureParms(DrawParms *parms, FTexture *img, double xx, double
 	return false;
 }
 
-static void ListEnd(va_list &tags)
+static void ListEnd(Va_List &tags)
 {
-	va_end(tags);
+	va_end(tags.list);
 }
 
-static int ListGetInt(va_list &tags)
+static int ListGetInt(Va_List &tags)
 {
-	return va_arg(tags, int);
+	return va_arg(tags.list, int);
 }
 
-static inline double ListGetDouble(va_list &tags)
+static inline double ListGetDouble(Va_List &tags)
 {
-	return va_arg(tags, double);
+	return va_arg(tags.list, double);
 }
 
 // These two options are only being used by the D3D version of the HUD weapon drawer, they serve no purpose anywhere else.
-static inline FSpecialColormap * ListGetSpecialColormap(va_list &tags)
+static inline FSpecialColormap * ListGetSpecialColormap(Va_List &tags)
 {
-	return va_arg(tags, FSpecialColormap *);
+	return va_arg(tags.list, FSpecialColormap *);
 }
 
-static inline FColormapStyle * ListGetColormapStyle(va_list &tags)
+static inline FColormapStyle * ListGetColormapStyle(Va_List &tags)
 {
-	return va_arg(tags, FColormapStyle *);
+	return va_arg(tags.list, FColormapStyle *);
 }
 
 static void ListEnd(VMVa_List &tags)
@@ -946,7 +946,7 @@ bool DCanvas::ParseDrawTextureTags(FTexture *img, double x, double y, DWORD tag,
 }
 // explicitly instantiate both versions for v_text.cpp.
 
-template bool DCanvas::ParseDrawTextureTags<va_list>(FTexture *img, double x, double y, DWORD tag, va_list& tags, DrawParms *parms, bool fortext) const;
+template bool DCanvas::ParseDrawTextureTags<Va_List>(FTexture *img, double x, double y, DWORD tag, Va_List& tags, DrawParms *parms, bool fortext) const;
 template bool DCanvas::ParseDrawTextureTags<VMVa_List>(FTexture *img, double x, double y, DWORD tag, VMVa_List& tags, DrawParms *parms, bool fortext) const;
 
 void DCanvas::VirtualToRealCoords(double &x, double &y, double &w, double &h,
diff --git a/src/v_text.cpp b/src/v_text.cpp
index 3394e448a..8b612e83c 100644
--- a/src/v_text.cpp
+++ b/src/v_text.cpp
@@ -71,10 +71,10 @@ void DCanvas::DrawChar (FFont *font, int normalcolor, double x, double y, int ch
 	if (NULL != (pic = font->GetChar (character, &dummy)))
 	{
 		DrawParms parms;
-		va_list tags;
-		va_start(tags, tag_first);
+		Va_List tags;
+		va_start(tags.list, tag_first);
 		bool res = ParseDrawTextureTags(pic, x, y, tag_first, tags, &parms, false);
-		va_end(tags);
+		va_end(tags.list);
 		if (!res)
 		{
 			return;
@@ -197,15 +197,15 @@ void DCanvas::DrawTextCommon(FFont *font, int normalcolor, double x, double y, c
 
 void DCanvas::DrawText(FFont *font, int normalcolor, double x, double y, const char *string, int tag_first, ...)
 {
-	va_list tags;
+	Va_List tags;
 	DrawParms parms;
 
 	if (font == NULL || string == NULL)
 		return;
 
-	va_start(tags, tag_first);
+	va_start(tags.list, tag_first);
 	bool res = ParseDrawTextureTags(nullptr, 0, 0, tag_first, tags, &parms, true);
-	va_end(tags);
+	va_end(tags.list);
 	if (!res)
 	{
 		return;
diff --git a/src/v_video.h b/src/v_video.h
index a594fa8fe..a2586d5a7 100644
--- a/src/v_video.h
+++ b/src/v_video.h
@@ -177,6 +177,11 @@ struct DrawParms
 	bool virtBottom;
 };
 
+struct Va_List
+{
+	va_list list;
+};
+
 struct VMVa_List
 {
 	VMValue *args;