shader: Properly manage attributes not written from previous stages

1 files changed, 5 insertions, 0 deletions

diff --git a/src/shader_recompiler/backend/glsl/emit_glsl_context_get_set.cpp b/src/shader_recompiler/backend/glsl/emit_glsl_context_get_set.cpp
index a241d18fe..663ff3753 100644
--- a/src/shader_recompiler/backend/glsl/emit_glsl_context_get_set.cpp
+++ b/src/shader_recompiler/backend/glsl/emit_glsl_context_get_set.cpp
@@ -8,6 +8,7 @@
 #include "shader_recompiler/backend/glsl/emit_glsl_instructions.h"
 #include "shader_recompiler/frontend/ir/value.h"
 #include "shader_recompiler/profile.h"
+#include "shader_recompiler/runtime_info.h"
 
 namespace Shader::Backend::GLSL {
 namespace {
@@ -179,6 +180,10 @@ void EmitGetAttribute(EmitContext& ctx, IR::Inst& inst, IR::Attribute attr,
     const char swizzle{"xyzw"[element]};
     if (IR::IsGeneric(attr)) {
         const u32 index{IR::GenericAttributeIndex(attr)};
+        if (!ctx.runtime_info.previous_stage_stores_generic[index]) {
+            ctx.AddF32("{}=0.f;", inst, attr);
+            return;
+        }
         ctx.AddF32("{}=in_attr{}{}.{};", inst, index, InputVertexIndex(ctx, vertex), swizzle);
         return;
     }