[Mesa-dev] [PATCH 14/23] glsl/ast: Forbid declaration of image variables in structures and uniform blocks.

[Francisco Jerez]

Aggregating images inside uniform blocks is explicitly disallowed by
the standard, aggregating them inside structures is not (as of GL
4.4), but there is a similar problem as with atomic counters: image
uniform declarations require either a "writeonly" memory qualifier or
an explicit format qualifier, which are explicitly forbidden in
structure member declarations.  In the resolution of Khronos bug
#10903 the same wording applied to atomic counters was decided to mean
that they're not allowed inside structures -- Rejecting image member
declarations within structures seems the most reasonable option for
now.
---
 src/glsl/ast_to_hir.cpp | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/glsl/ast_to_hir.cpp b/src/glsl/ast_to_hir.cpp
index 1d13a2c..b421b81 100644
--- a/src/glsl/ast_to_hir.cpp
+++ b/src/glsl/ast_to_hir.cpp
@@ -4693,6 +4693,16 @@ ast_process_structure_or_interface_block(exec_list *instructions,
                              "uniform block");
          }
 
+         if (field_type->contains_image()) {
+            /* FINISHME: Same problem as with atomic counters.
+             * FINISHME: Request clarification from Khronos and add
+             * FINISHME: spec quotation here.
+             */
+            YYLTYPE loc = decl_list->get_location();
+            _mesa_glsl_error(&loc, state,
+                             "image in structure or uniform block");
+         }
+
          const struct ast_type_qualifier *const qual =
             & decl_list->type->qualifier;
          if (qual->flags.q.std140 ||
-- 
1.8.3.4