[Mesa-dev] [PATCH 3/9] glsl: Emit errors for things that look like default precision statements

[Ian Romanick]

From: Ian Romanick <ian.d.romanick at intel.com>

Previously we would emit a warning for empty declarations like

float;

We would also emit the same warning for things like

highp float;

However, this second case is most likely the application trying to set the
default precision.  We should instead generate an error.

Fixes piglit precision-05.vert.

Signed-off-by: Ian Romanick <ian.d.romanick at intel.com>
Cc: "9.2" <mesa-stable at lists.freedesktop.org>
---
 src/glsl/ast_to_hir.cpp | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/src/glsl/ast_to_hir.cpp b/src/glsl/ast_to_hir.cpp
index 49804b7..9d2ffff 100644
--- a/src/glsl/ast_to_hir.cpp
+++ b/src/glsl/ast_to_hir.cpp
@@ -2697,6 +2697,10 @@ ast_declarator_list::hir(exec_list *instructions,
        *   name of a known structure type.  This is both invalid and weird.
        *   Emit an error.
        *
+       * - The program text contained something like 'mediump float;'
+       *   when the programmer probably meant 'precision mediump
+       *   float;' Emit an error.
+       *
        * Note that if decl_type is NULL and there is a structure involved,
        * there must have been some sort of error with the structure.  In this
        * case we assume that an error was already generated on this line of
@@ -2705,7 +2709,10 @@ ast_declarator_list::hir(exec_list *instructions,
        */
       assert(this->type->specifier->structure == NULL || decl_type != NULL
 	     || state->error);
-      if (this->type->specifier->structure == NULL) {
+      if (this->type->qualifier.precision != ast_precision_none) {
+         _mesa_glsl_error(&loc, state,
+                          "set default precision using `precision' keyword");
+      } else if (this->type->specifier->structure == NULL) {
 	 if (decl_type != NULL) {
 	    _mesa_glsl_warning(&loc, state, "empty declaration");
 	 } else {
@@ -2714,12 +2721,6 @@ ast_declarator_list::hir(exec_list *instructions,
 			     type_name);
 	 }
       }
-
-      if (this->type->qualifier.precision != ast_precision_none &&
-          this->type->specifier->structure != NULL) {
-         _mesa_glsl_error(&loc, state, "precision qualifiers can't be applied "
-                          "to structures");
-      }
    }
 
    foreach_list_typed (ast_declaration, decl, link, &this->declarations) {
-- 
1.8.1.4