4 files changed, 27 insertions, 7 deletions
diff --git a/scripts/kconfig/lkc_proto.h b/scripts/kconfig/lkc_proto.h
index 2b16d6e1b2db..6303193f43f2 100644
--- a/scripts/kconfig/lkc_proto.h
+++ b/scripts/kconfig/lkc_proto.h
@@ -49,8 +49,13 @@ const char * sym_get_string_value(struct symbol *sym);
 const char * prop_get_type_name(enum prop_type type);
 
 /* preprocess.c */
+enum variable_flavor {
+	VAR_SIMPLE,
+	VAR_RECURSIVE,
+};
 void env_write_dep(FILE *f, const char *auto_conf_name);
-void variable_add(const char *name, const char *value);
+void variable_add(const char *name, const char *value,
+		  enum variable_flavor flavor);
 void variable_all_del(void);
 char *expand_string(const char *in);
 char *expand_dollar(const char **str);
diff --git a/scripts/kconfig/preprocess.c b/scripts/kconfig/preprocess.c
index 46487fe6b36c..d103683b386e 100644
--- a/scripts/kconfig/preprocess.c
+++ b/scripts/kconfig/preprocess.c
@@ -185,6 +185,7 @@ static LIST_HEAD(variable_list);
 struct variable {
 	char *name;
 	char *value;
+	enum variable_flavor flavor;
 	struct list_head node;
 };
 
@@ -203,15 +204,22 @@ static struct variable *variable_lookup(const char *name)
 static char *variable_expand(const char *name, int argc, char *argv[])
 {
 	struct variable *v;
+	char *res;
 
 	v = variable_lookup(name);
 	if (!v)
 		return NULL;
 
-	return expand_string_with_args(v->value, argc, argv);
+	if (v->flavor == VAR_RECURSIVE)
+		res = expand_string_with_args(v->value, argc, argv);
+	else
+		res = xstrdup(v->value);
+
+	return res;
 }
 
-void variable_add(const char *name, const char *value)
+void variable_add(const char *name, const char *value,
+		  enum variable_flavor flavor)
 {
 	struct variable *v;
 
@@ -224,7 +232,12 @@ void variable_add(const char *name, const char *value)
 		list_add_tail(&v->node, &variable_list);
 	}
 
-	v->value = xstrdup(value);
+	v->flavor = flavor;
+
+	if (flavor == VAR_SIMPLE)
+		v->value = expand_string(value);
+	else
+		v->value = xstrdup(value);
 }
 
 static void variable_del(struct variable *v)
diff --git a/scripts/kconfig/zconf.l b/scripts/kconfig/zconf.l
index dd08f7a38ccd..376af6cf2f65 100644
--- a/scripts/kconfig/zconf.l
+++ b/scripts/kconfig/zconf.l
@@ -114,7 +114,8 @@ n	[A-Za-z0-9_-]
 		yylval.string = text;
 		return T_VARIABLE;
 	}
-	"="	{ BEGIN(ASSIGN_VAL); return T_ASSIGN; }
+	"="	{ BEGIN(ASSIGN_VAL); yylval.flavor = VAR_RECURSIVE; return T_ASSIGN; }
+	":="	{ BEGIN(ASSIGN_VAL); yylval.flavor = VAR_SIMPLE; return T_ASSIGN; }
 	[[:blank:]]+
 	.	warn_ignored_character(*yytext);
 	\n	{
diff --git a/scripts/kconfig/zconf.y b/scripts/kconfig/zconf.y
index e15e8c7063e0..6f9b0aa32a82 100644
--- a/scripts/kconfig/zconf.y
+++ b/scripts/kconfig/zconf.y
@@ -41,6 +41,7 @@ static struct menu *current_menu, *current_entry;
 	struct expr *expr;
 	struct menu *menu;
 	const struct kconf_id *id;
+	enum variable_flavor flavor;
 }
 
 %token <id>T_MAINMENU
@@ -78,7 +79,7 @@ static struct menu *current_menu, *current_entry;
 %token T_OPEN_PAREN
 %token T_EOL
 %token <string> T_VARIABLE
-%token T_ASSIGN
+%token <flavor> T_ASSIGN
 %token <string> T_ASSIGN_VAL
 
 %left T_OR
@@ -517,7 +518,7 @@ word_opt: /* empty */			{ $$ = NULL; }
 
 /* assignment statement */
 
-assignment_stmt:  T_VARIABLE T_ASSIGN assign_val T_EOL	{ variable_add($1, $3); free($1); free($3); }
+assignment_stmt:  T_VARIABLE T_ASSIGN assign_val T_EOL	{ variable_add($1, $3, $2); free($1); free($3); }
 
 assign_val:
 	/* empty */		{ $$ = xstrdup(""); };