Currently, Kconfig does not report anything about the recursive dependency where 'imply' keywords are involved. [Test Code] config A bool "a" config B bool "b" imply A depends on A In the code above, Kconfig cannot calculate the symbol values correctly due to the circular dependency. For example, allyesconfig followed by syncconfig results in an odd behavior because CONFIG_B becomes visible in syncconfig. $ make allyesconfig scripts/kconfig/conf --allyesconfig Kconfig # # configuration written to .config # $ cat .config # # Automatically generated file; DO NOT EDIT. # Main menu # CONFIG_A=y $ make syncconfig scripts/kconfig/conf --syncconfig Kconfig * * Restart config... * * * Main menu * a (A) [Y/n/?] y b (B) [N/y/?] (NEW) To report this correctly, sym_check_expr_deps() should recurse to not only sym->rev_dep.expr but also sym->implied.expr . At this moment, sym_check_print_recursive() cannot distinguish 'select' and 'imply' since it does not know the precise context where the recursive dependency is hit. This will be solved by the next commit. Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> --- scripts/kconfig/symbol.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/scripts/kconfig/symbol.c b/scripts/kconfig/symbol.c index 4ec8b1f..7de7463a 100644 --- a/scripts/kconfig/symbol.c +++ b/scripts/kconfig/symbol.c @@ -1098,7 +1098,7 @@ static void sym_check_print_recursive(struct symbol *last_sym) sym->name ? sym->name : "<choice>", next_sym->name ? next_sym->name : "<choice>"); } else { - fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n", + fprintf(stderr, "%s:%d:\tsymbol %s is selected or implied by %s\n", prop->file->name, prop->lineno, sym->name ? sym->name : "<choice>", next_sym->name ? next_sym->name : "<choice>"); @@ -1161,8 +1161,13 @@ static struct symbol *sym_check_sym_deps(struct symbol *sym) if (sym2) goto out; + sym2 = sym_check_expr_deps(sym->implied.expr); + if (sym2) + goto out; + for (prop = sym->prop; prop; prop = prop->next) { - if (prop->type == P_CHOICE || prop->type == P_SELECT) + if (prop->type == P_CHOICE || prop->type == P_SELECT || + prop->type == P_IMPLY) continue; stack.prop = prop; sym2 = sym_check_expr_deps(prop->visible.expr); -- 2.7.4