glsl: avoid compiler's segfault when processing operators with void arguments
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 assignment of a void variable which will be optimized out (the assignment) 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. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=85252 Signed-off-by:Renaud Gaubert <renaud@lse.epita.fr> Reviewed-by:
Gabriel Laskar <gabriel@lse.epita.fr> Reviewed-by:
Samuel Iglesias Gonsalvez <siglesias@igalia.com>