[gtk+/wip/otte/shader: 233/269] gskslexpression: Function arguments are evaluated randomly

[Benjamin Otte <otte src gnome org>]

commit 3bd9c7ebb5736fa43f1bb60db99cdb622624786a
Author: Benjamin Otte <otte redhat com>
Date:   Mon Oct 16 02:31:45 2017 +0200

    gskslexpression: Function arguments are evaluated randomly
    
    The C spec doesn't guarantee an order of evaluation for function
    arguments. In fact, gcc evaluates them last to first while clang
    evaluated them first to last.
    
    We would like the left argument to be written into the SPIRV file first
    (the GLSL spec wants that), so enforce this by calling the functions
    before.

 gsk/gskslexpression.c |    8 ++++++--
 1 files changed, 6 insertions(+), 2 deletions(-)
---
diff --git a/gsk/gskslexpression.c b/gsk/gskslexpression.c
index 60c88ac..148acd2 100644
--- a/gsk/gskslexpression.c
+++ b/gsk/gskslexpression.c
@@ -266,14 +266,18 @@ gsk_sl_expression_binary_write_spv (const GskSlExpression *expression,
                                     GskSpvWriter          *writer)
 {
   const GskSlExpressionBinary *binary = (const GskSlExpressionBinary *) expression;
+  guint left_id, right_id;
+
+  left_id = gsk_sl_expression_write_spv (binary->left, writer);
+  right_id = gsk_sl_expression_write_spv (binary->right, writer);
 
   return gsk_sl_binary_write_spv (binary->binary,
                                   writer,
                                   binary->type,
                                   gsk_sl_expression_get_return_type (binary->left),
-                                  gsk_sl_expression_write_spv (binary->left, writer),
+                                  left_id,
                                   gsk_sl_expression_get_return_type (binary->right),
-                                  gsk_sl_expression_write_spv (binary->right, writer));
+                                  right_id);
 }
 
 static const GskSlExpressionClass GSK_SL_EXPRESSION_BINARY = {