From 2d8ca6673a8f66aa10b7acc7786e6331de3c9cc0 Mon Sep 17 00:00:00 2001 From: Kamil Dudka Date: Wed, 26 May 2010 02:14:23 +0200 Subject: [PATCH] issue warnings for implied casts to bool [unstable] Signed-off-by: Kamil Dudka --- evaluate.c | 34 ++++++++++++++++++++++++++++++++++ 1 files changed, 34 insertions(+), 0 deletions(-) diff --git a/evaluate.c b/evaluate.c index cdbd064..9532ab5 100644 --- a/evaluate.c +++ b/evaluate.c @@ -256,6 +256,38 @@ warn_for_different_enum_types (struct position pos, } } +static void +warn_for_implied_cast_to_bool(struct expression *expr, struct symbol *typeb) +{ + struct symbol *typea = expr->ctype; + switch (expr->type) { + case EXPR_SELECT: + case EXPR_CONDITIONAL: + // FIXME: we are not ready for conditional expressions + return; + + case EXPR_VALUE: + if (expr->value == 0 || expr->value == 1) + return; + // fall through! + + default: + if (typea->type == SYM_NODE) + typea = typea->ctype.base_type; + if (typeb->type == SYM_NODE) + typeb = typeb->ctype.base_type; + + // we are interested only in implied casts to bool + if (typea != &bool_ctype && typeb == &bool_ctype) + { + const char *a = strdup(show_typename(typea)); + const char *b = show_typename(typeb); + warning(expr->pos, "implied cast from %s to %s", a, b); + free((char *) a); + } + } +} + /* * This gets called for implicit casts in assignments and * integer promotion. We often want to try to move the @@ -305,6 +337,8 @@ static struct expression * cast_to(struct expression *old, struct symbol *type) /* nothing */; } + warn_for_implied_cast_to_bool(old, type); + expr = alloc_expression(old->pos, EXPR_IMPLIED_CAST); expr->flags = old->flags; expr->ctype = type; -- 1.7.1