General demurrers shall not be used. Every defect, omission or fault in a pleading either of form or of substance, which is not specifically pointed out by exception in writing and brought to the attention of the judge in the trial court before the instruction or charge to the jury or, in a non-jury case, before the judgment is signed, shall be deemed to have been waived by the party seeking reversal on such account; provided that this rule shall not apply as to any party against whom default judgment is rendered.
Tex. R. Civ. P. 90