This is done by returning an rvalue of type void in the ast_function_expression::hir function instead of a void expression.
This produces (in the case of the ternary) an hir with a call to the void returning function and an assignement of a void variable which will be optimized out (the assignement) during the optimization pass. This fix results in having a valid subexpression in the many different cases where the subexpressions are functions whose return values are void. Thus preventing to dereference NULL in the following cases: * binary operator * unary operators * ternary operator * comparison operators (except equal and nequal operator) Equal and nequal had to be handled as a special case because instead of segfaulting on a forbidden syntax it was now accepting expressions with a void return value on either (or both) side of the expression. Piglist tests are on the way Signed-off-by: Renaud Gaubert <ren...@lse.epita.fr> Reviewed-by: Gabriel Laskar <gabr...@lse.epita.fr> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=85252 --- src/glsl/ast_function.cpp | 6 +++++- src/glsl/ast_to_hir.cpp | 10 +++++++++- 2 files changed, 14 insertions(+), 2 deletions(-) diff --git a/src/glsl/ast_function.cpp b/src/glsl/ast_function.cpp index 92e26bf..776a754 100644 --- a/src/glsl/ast_function.cpp +++ b/src/glsl/ast_function.cpp @@ -1785,7 +1785,11 @@ ast_function_expression::hir(exec_list *instructions, /* an error has already been emitted */ value = ir_rvalue::error_value(ctx); } else { - value = generate_call(instructions, sig, &actual_parameters, state); + value = generate_call(instructions, sig, &actual_parameters, state); + if (!value) { + ir_variable *const tmp = new(ctx) ir_variable(glsl_type::void_type, "void_var", ir_var_temporary); + value = new(ctx) ir_dereference_variable(tmp); + } } return value; diff --git a/src/glsl/ast_to_hir.cpp b/src/glsl/ast_to_hir.cpp index 8cb46be..00cc16c 100644 --- a/src/glsl/ast_to_hir.cpp +++ b/src/glsl/ast_to_hir.cpp @@ -1270,7 +1270,15 @@ ast_expression::do_hir(exec_list *instructions, * applied to one operand that can make them match, in which * case this conversion is done." */ - if ((!apply_implicit_conversion(op[0]->type, op[1], state) + + if (op[0]->type == glsl_type::void_type || op[1]->type == glsl_type::void_type) { + + _mesa_glsl_error(& loc, state, "`%s': wrong operand types: no operation " + "`%1$s' exists that takes a left-hand operand of type 'void' or a " + "right operand of type 'void'", (this->oper == ast_equal) ? "==" : "!="); + + error_emitted = true; + } else if ((!apply_implicit_conversion(op[0]->type, op[1], state) && !apply_implicit_conversion(op[1]->type, op[0], state)) || (op[0]->type != op[1]->type)) { _mesa_glsl_error(& loc, state, "operands of `%s' must have the same " -- 2.4.5 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
