kconfig: simplify select-with-unmet-direct-dependency warning
This is an attempt to simplify the expressing printed by kconfig when a
symbol is selected but still has direct unmet dependency.
First, the symbol reverse dependency is split in sub-expression. Then,
each sub-expression is checked to ensure that it does not contains the
unmet dependency. This removes the false-positive symbols and fixed symbol
which already have the correct dependency. Finally, only the symbol
responsible of the "select" is printed, instead of its full dependency tree.
CC: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
diff --git a/scripts/kconfig/expr.c b/scripts/kconfig/expr.c
index 330e7c0..65531a7 100644
--- a/scripts/kconfig/expr.c
+++ b/scripts/kconfig/expr.c
@@ -1013,6 +1013,48 @@
#endif
}
+static inline struct expr *
+expr_get_leftmost_symbol(const struct expr *e)
+{
+
+ if (e == NULL)
+ return NULL;
+
+ while (e->type != E_SYMBOL)
+ e = e->left.expr;
+
+ return expr_copy(e);
+}
+
+/*
+ * Given expression `e1' and `e2', returns the leaf of the longest
+ * sub-expression of `e1' not containing 'e2.
+ */
+struct expr *expr_simplify_unmet_dep(struct expr *e1, struct expr *e2)
+{
+ struct expr *ret;
+
+ switch (e1->type) {
+ case E_OR:
+ return expr_alloc_and(
+ expr_simplify_unmet_dep(e1->left.expr, e2),
+ expr_simplify_unmet_dep(e1->right.expr, e2));
+ case E_AND: {
+ struct expr *e;
+ e = expr_alloc_and(expr_copy(e1), expr_copy(e2));
+ e = expr_eliminate_dups(e);
+ ret = (!expr_eq(e, e1)) ? e1 : NULL;
+ expr_free(e);
+ break;
+ }
+ default:
+ ret = e1;
+ break;
+ }
+
+ return expr_get_leftmost_symbol(ret);
+}
+
void expr_print(struct expr *e, void (*fn)(void *, struct symbol *, const char *), void *data, int prevtoken)
{
if (!e) {