3 files changed, 25 insertions, 0 deletions

diff --git a/scripts/kconfig/expr.h b/scripts/kconfig/expr.h
index 891cd9ce9ba2..75a31e4552f3 100644
--- a/scripts/kconfig/expr.h
+++ b/scripts/kconfig/expr.h
@@ -83,6 +83,7 @@ struct symbol {
         tristate visible;
         int flags;
         struct property *prop;
+        struct expr_value dir_dep;
         struct expr_value rev_dep;
 };
 
@@ -163,6 +164,7 @@ struct menu {
         struct symbol *sym;
         struct property *prompt;
         struct expr *dep;
+        struct expr *dir_dep;
         unsigned int flags;
         char *help;
         struct file *file;
diff --git a/scripts/kconfig/menu.c b/scripts/kconfig/menu.c
index eef17bacb6bc..11799894f3bd 100644
--- a/scripts/kconfig/menu.c
+++ b/scripts/kconfig/menu.c
@@ -105,6 +105,7 @@ static struct expr *menu_check_dep(struct expr *e)
 void menu_add_dep(struct expr *dep)
 {
         current_entry->dep = expr_alloc_and(current_entry->dep, menu_check_dep(dep));
+        current_entry->dir_dep = current_entry->dep;
 }
 
 void menu_set_type(int type)
@@ -288,6 +289,10 @@ void menu_finalize(struct menu *parent)
                 for (menu = parent->list; menu; menu = menu->next)
                         menu_finalize(menu);
         } else if (sym) {
+                /* ignore inherited dependencies for dir_dep */
+                sym->dir_dep.expr = expr_transform(expr_copy(parent->dir_dep));
+                sym->dir_dep.expr = expr_eliminate_dups(sym->dir_dep.expr);
+
                 basedep = parent->prompt ? parent->prompt->visible.expr : NULL;
                 basedep = expr_trans_compare(basedep, E_UNEQUAL, &symbol_no);
                 basedep = expr_eliminate_dups(expr_transform(basedep));
diff --git a/scripts/kconfig/symbol.c b/scripts/kconfig/symbol.c
index 2e7a048e0cfc..174b230a52b0 100644
--- a/scripts/kconfig/symbol.c
+++ b/scripts/kconfig/symbol.c
@@ -205,6 +205,16 @@ static void sym_calc_visibility(struct symbol *sym)
         }
         if (sym_is_choice_value(sym))
                 return;
+        /* defaulting to "yes" if no explicit "depends on" are given */
+        tri = yes;
+        if (sym->dir_dep.expr)
+                tri = expr_calc_value(sym->dir_dep.expr);
+        if (tri == mod)
+                tri = yes;
+        if (sym->dir_dep.tri != tri) {
+                sym->dir_dep.tri = tri;
+                sym_set_changed(sym);
+        }
         tri = no;
         if (sym->rev_dep.expr)
                 tri = expr_calc_value(sym->rev_dep.expr);
@@ -321,6 +331,14 @@ void sym_calc_value(struct symbol *sym)
                                 }
                         }
                 calc_newval:
+                        if (sym->dir_dep.tri == no && sym->rev_dep.tri != no) {
+                                fprintf(stderr, "warning: (");
+                                expr_fprint(sym->rev_dep.expr, stderr);
+                                fprintf(stderr, ") selects %s which has unmet direct dependencies (",
+                                        sym->name);
+                                expr_fprint(sym->dir_dep.expr, stderr);
+                                fprintf(stderr, ")\n");
+                        }
                         newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
                 }
                 if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)