diff --git a/src/compiler/glsl/link_varyings.cpp b/src/compiler/glsl/link_varyings.cpp
index 51b1f432d4d..9954a731479 100644
--- a/src/compiler/glsl/link_varyings.cpp
+++ b/src/compiler/glsl/link_varyings.cpp
@@ -739,6 +739,44 @@ validate_first_and_last_interface_explicit_locations(struct gl_context *ctx,
    }
 }
 
+/**
+ * Check if we should force input / output matching between shader
+ * interfaces.
+ *
+ * Section 4.3.4 (Inputs) of the GLSL 4.10 specifications say:
+ *
+ *   "Only the input variables that are actually read need to be
+ *    written by the previous stage; it is allowed to have
+ *    superfluous declarations of input variables."
+ *
+ * However it's not defined anywhere as to how we should handle
+ * inputs that are not written in the previous stage and it's not
+ * clear what "actually read" means.
+ *
+ * The GLSL 4.20 spec however is much clearer:
+ *
+ *    "Only the input variables that are statically read need to
+ *     be written by the previous stage; it is allowed to have
+ *     superfluous declarations of input variables."
+ *
+ * It also has a table that states it is an error to statically
+ * read an input that is not defined in the previous stage. While
+ * it is not an error to not statically write to the output (it
+ * just needs to be defined to not be an error).
+ *
+ * The text in the GLSL 4.20 spec was an attempt to clarify the
+ * previous spec iterations. However given the difference in spec
+ * and that some applications seem to depend on not erroring when
+ * the input is not actually read in control flow we only apply
+ * this rule to GLSL 4.20 and higher. GLSL 4.10 shaders have been
+ * seen in the wild that depend on the less strict interpretation.
+ */
+static bool
+static_input_output_matching(struct gl_shader_program *prog)
+{
+   return prog->data->Version >= (prog->IsES ? 0 : 420);
+}
+
 /**
  * Validate that outputs from one stage match inputs of another
  */
@@ -847,7 +885,7 @@ cross_validate_outputs_to_inputs(struct gl_context *ctx,
                    * output declaration and there is Static Use of the
                    * declared input.
                    */
-                  if (input->data.used) {
+                  if (input->data.used && static_input_output_matching(prog)) {
                      linker_error(prog,
                                   "%s shader input `%s' with explicit location "
                                   "has no matching output\n",
@@ -882,40 +920,11 @@ cross_validate_outputs_to_inputs(struct gl_context *ctx,
             /* Check for input vars with unmatched output vars in prev stage
              * taking into account that interface blocks could have a matching
              * output but with different name, so we ignore them.
-             *
-             * Section 4.3.4 (Inputs) of the GLSL 4.10 specifications say:
-             *
-             *   "Only the input variables that are actually read need to be
-             *    written by the previous stage; it is allowed to have
-             *    superfluous declarations of input variables."
-             *
-             * However it's not defined anywhere as to how we should handle
-             * inputs that are not written in the previous stage and it's not
-             * clear what "actually read" means.
-             *
-             * The GLSL 4.20 spec however is much clearer:
-             *
-             *    "Only the input variables that are statically read need to
-             *     be written by the previous stage; it is allowed to have
-             *     superfluous declarations of input variables."
-             *
-             * It also has a table that states it is an error to statically
-             * read an input that is not defined in the previous stage. While
-             * it is not an error to not statically write to the output (it
-             * just needs to be defined to not be an error).
-             *
-             * The text in the GLSL 4.20 spec was an attempt to clarify the
-             * previous spec iterations. However given the difference in spec
-             * and that some applications seem to depend on not erroring when
-             * the input is not actually read in control flow we only apply
-             * this rule to GLSL 4.00 and higher. GLSL 4.00 was chosen as
-             * a 3.30 shader is the highest version of GLSL we have seen in
-             * the wild dependant on the less strict interpretation.
              */
             assert(!input->data.assigned);
             if (input->data.used && !input->get_interface_type() &&
                 !input->data.explicit_location &&
-                (prog->data->Version >= (prog->IsES ? 0 : 400)))
+                static_input_output_matching(prog))
                linker_error(prog,
                             "%s shader input `%s' "
                             "has no matching output in the previous stage\n",