[Mesa-dev] [PATCH] glsl: reject samplers not declared as uniform/function parameters

[Samuel Pitoiset]

>From section 4.1.7 of the GLSL 4.40 spec:

   "The opaque types declare variables that are effectively opaque
   handles to other objects.  These objects are accessed through
   built-in functions, not through direct reading or writing of
   the declared variable.  They  can only be declared as function
   parameters or in uniform- qualified variables."

Image variables and atomic counters are already rejected in this
situation.

Note that opaque variables can't be treated as l-values, which
means only the 'in' function parameter is allowed.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset at gmail.com>
---
 src/compiler/glsl/ast_to_hir.cpp | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/compiler/glsl/ast_to_hir.cpp b/src/compiler/glsl/ast_to_hir.cpp
index 22803e89c7..3279149d34 100644
--- a/src/compiler/glsl/ast_to_hir.cpp
+++ b/src/compiler/glsl/ast_to_hir.cpp
@@ -3601,6 +3601,15 @@ apply_layout_qualifier_to_variable(const struct ast_type_qualifier *qual,
       }
    }
 
+   if (var->type->contains_sampler()) {
+      if (var->data.mode != ir_var_uniform &&
+          var->data.mode != ir_var_function_in) {
+         _mesa_glsl_error(loc, state, "sampler variables may only be declared "
+                          "as function parameters or uniform-qualified "
+                          "global variables");
+      }
+   }
+
    /* Is the 'layout' keyword used with parameters that allow relaxed checking.
     * Many implementations of GL_ARB_fragment_coord_conventions_enable and some
     * implementations (only Mesa?) GL_ARB_explicit_attrib_location_enable
-- 
2.11.1