[Mesa-dev] [PATCH 2/2] glsl/es31: precision qualifier doesn't need to match in shader interface block members

[Samuel Iglesias Gonsálvez]

It is specific only to GLSL ES 3.1. From the spec, section 4.3.9
"Interface Blocks":

"Matched block names within a shader interface (as defined above) must
 match in terms of having the same number of declarations with the same
 sequence of types and the same sequence of member names, as well as
 having the same qualification as specified in section 9.2 (“Matching
 of Qualifiers“)."

But in GLSL ES 3.0 and 3.2, it is the opposite:

"Matched block names within a shader interface (as defined above) must
 match in terms of having the same number of declarations with the same
 sequence of types, precisions and the same sequence of member names,
 as well as having the matching member-wise layout qualification as
 defined in section 9.2 (“Matching of Qualifiers”)."

Fixes:

dEQP-GLES31.functional.shaders.linkage.uniform.block.differing_precision

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98243
Signed-off-by: Samuel Iglesias Gonsálvez <siglesias at igalia.com>
---
 src/compiler/glsl/link_interface_blocks.cpp |  7 +++++--
 src/compiler/glsl/linker.cpp                | 10 +++++++++-
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/src/compiler/glsl/link_interface_blocks.cpp b/src/compiler/glsl/link_interface_blocks.cpp
index 9a0b6ec..a176c3b 100644
--- a/src/compiler/glsl/link_interface_blocks.cpp
+++ b/src/compiler/glsl/link_interface_blocks.cpp
@@ -112,8 +112,11 @@ intrastage_match(ir_variable *a,
        * don't force their types to match.  They might mismatch due to the two
        * shaders using different GLSL versions, and that's ok.
        */
-      if (a->data.how_declared != ir_var_declared_implicitly ||
-          b->data.how_declared != ir_var_declared_implicitly)
+      if ((a->data.how_declared != ir_var_declared_implicitly ||
+           b->data.how_declared != ir_var_declared_implicitly) &&
+          (!prog->IsES || prog->Version != 310 ||
+           interstage_member_mismatch(prog, a->get_interface_type(),
+                                      b->get_interface_type())))
          return false;
    }
 
diff --git a/src/compiler/glsl/linker.cpp b/src/compiler/glsl/linker.cpp
index 8599590..0b3c195 100644
--- a/src/compiler/glsl/linker.cpp
+++ b/src/compiler/glsl/linker.cpp
@@ -1063,7 +1063,15 @@ cross_validate_globals(struct gl_shader_program *prog,
             return;
          }
 
-         if (prog->IsES && existing->data.precision != var->data.precision) {
+         /* Only in GLSL ES 3.10, the precision qualifier should not match
+          * between block members defined in matched block names within a
+          * shader interface.
+          *
+          * In GLSL ES 3.00 and ES 3.20, precision qualifier for each block
+          * member should match.
+          */
+         if (prog->IsES && (prog->Version != 310 || !var->get_interface_type()) &&
+             existing->data.precision != var->data.precision) {
             linker_error(prog, "declarations for %s `%s` have "
                          "mismatching precision qualifiers\n",
                          mode_string(var), var->name);
-- 
2.7.4