diff --git a/imgui_draw.cpp b/imgui_draw.cpp
index 3a934eab..958cdbe8 100644
--- a/imgui_draw.cpp
+++ b/imgui_draw.cpp
@@ -1617,7 +1617,7 @@ bool    ImFontAtlasBuildWithStbTruetype(ImFontAtlas* atlas)
 
     // Start packing
     const int max_tex_height = 1024*32;
-    stbtt_pack_context spc;
+    stbtt_pack_context spc = {};
     stbtt_PackBegin(&spc, NULL, atlas->TexWidth, max_tex_height, 0, atlas->TexGlyphPadding, NULL);
     stbtt_PackSetOversampling(&spc, 1, 1);