diff --git a/renderdoc/data/glsl/gl_texsample.h b/renderdoc/data/glsl/gl_texsample.h
index a724fde43..9ce052024 100644
--- a/renderdoc/data/glsl/gl_texsample.h
+++ b/renderdoc/data/glsl/gl_texsample.h
@@ -252,6 +252,8 @@ vec4 SampleTextureFloat4(int type, vec2 pos, float slice, int mipLevel, int samp
     {
       int sampleCount = -sampleIdx;
 
+      col = vec4(0, 0, 0, 0);
+
       // worst resolve you've seen in your life
       // it's manually unrolled because doing it as a dynamic loop on
       // sampleCount seems to produce crazy artifacts on nvidia - probably a compiler bug
@@ -313,6 +315,8 @@ vec4 SampleTextureFloat4(int type, vec2 pos, float slice, int mipLevel, int samp
     {
       int sampleCount = -sampleIdx;
 
+      col = vec4(0, 0, 0, 0);
+
       // worst resolve you've seen in your life
       // it's manually unrolled because doing it as a dynamic loop on
       // sampleCount seems to produce crazy artifacts on nvidia - probably a compiler bug