[Mesa-dev] [PATCH] glsl: Add a citation for uniform precision matching.

[Kenneth Graunke]

Ian added this check in commit 259fc505454ea6a67aeacf6cdebf1398d9947759.
While reviewing the rules, I found a citation which spells this out
clearly, so I figured I'd send a patch to add it as a comment.

Cc: idr at freedesktop.org
Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
---
 src/compiler/glsl/linker.cpp | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/compiler/glsl/linker.cpp b/src/compiler/glsl/linker.cpp
index c95edf3..78c9ea8 100644
--- a/src/compiler/glsl/linker.cpp
+++ b/src/compiler/glsl/linker.cpp
@@ -1154,6 +1154,14 @@ cross_validate_globals(struct gl_shader_program *prog,
             return;
          }
 
+         /* The GLSL ES 3.2 specification says:
+          *
+          *    "Uniforms in shaders all share a single global name space when
+          *     linked into a program or separable program. Hence, the types,
+          *     precisions and any location specifiers of all declared uniform
+          *     variables with the same name must match across shaders that
+          *     are linked into a single program."
+          */
          if (prog->IsES && existing->data.precision != var->data.precision) {
             linker_error(prog, "declarations for %s `%s` have "
                          "mismatching precision qualifiers\n",
-- 
2.9.3