kconfig: error out when seeing recursive dependency

Originally, recursive dependency was a fatal error for Kconfig
because Kconfig cannot compute symbol values in such a situation.

Commit d595cea62403 ("kconfig: print more info when we see a recursive
dependency") changed it to a warning, which I guess was not intentional.

Get it back to an error again.

Also, rename the unit test directory "warn_recursive_dep" to
"err_recursive_dep" so that it matches to the behavior.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Dirk Gouders <dirk@gouders.net>

3 files changed, 102 insertions, 0 deletions

diff --git a/scripts/kconfig/tests/err_recursive_dep/Kconfig b/scripts/kconfig/tests/err_recursive_dep/Kconfig
new file mode 100644
index 000000000000..a65bfcb7137e
--- /dev/null
+++ b/scripts/kconfig/tests/err_recursive_dep/Kconfig
@@ -0,0 +1,62 @@
+# depends on itself
+
+config A
+	bool "A"
+	depends on A
+
+# select itself
+
+config B
+	bool
+	select B
+
+# depends on each other
+
+config C1
+	bool "C1"
+	depends on C2
+
+config C2
+	bool "C2"
+	depends on C1
+
+# depends on and select
+
+config D1
+	bool "D1"
+	depends on D2
+	select D2
+
+config D2
+	bool
+
+# depends on and imply
+# This is not recursive dependency
+
+config E1
+	bool "E1"
+	depends on E2
+	imply E2
+
+config E2
+	bool "E2"
+
+# property
+
+config F1
+	bool "F1"
+	default F2
+
+config F2
+	bool "F2"
+	depends on F1
+
+# menu
+
+menu "menu depending on its content"
+	depends on G
+
+config G
+	bool "G"
+
+endmenu
diff --git a/scripts/kconfig/tests/err_recursive_dep/__init__.py b/scripts/kconfig/tests/err_recursive_dep/__init__.py
new file mode 100644
index 000000000000..5f3821b43ce6
--- /dev/null
+++ b/scripts/kconfig/tests/err_recursive_dep/__init__.py
@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: GPL-2.0
+"""
+Detect recursive dependency error.
+
+Recursive dependency should be treated as an error.
+"""
+
+def test(conf):
+    assert conf.oldaskconfig() == 1
+    assert conf.stderr_contains('expected_stderr')
diff --git a/scripts/kconfig/tests/err_recursive_dep/expected_stderr b/scripts/kconfig/tests/err_recursive_dep/expected_stderr
new file mode 100644
index 000000000000..3de807dd9cb2
--- /dev/null
+++ b/scripts/kconfig/tests/err_recursive_dep/expected_stderr
@@ -0,0 +1,30 @@
+Kconfig:9:error: recursive dependency detected!
+Kconfig:9:	symbol B is selected by B
+For a resolution refer to Documentation/kbuild/kconfig-language.txt
+subsection "Kconfig recursive dependency limitations"
+
+Kconfig:3:error: recursive dependency detected!
+Kconfig:3:	symbol A depends on A
+For a resolution refer to Documentation/kbuild/kconfig-language.txt
+subsection "Kconfig recursive dependency limitations"
+
+Kconfig:15:error: recursive dependency detected!
+Kconfig:15:	symbol C1 depends on C2
+Kconfig:19:	symbol C2 depends on C1
+For a resolution refer to Documentation/kbuild/kconfig-language.txt
+subsection "Kconfig recursive dependency limitations"
+
+Kconfig:30:error: recursive dependency detected!
+Kconfig:30:	symbol D2 is selected by D1
+Kconfig:25:	symbol D1 depends on D2
+For a resolution refer to Documentation/kbuild/kconfig-language.txt
+subsection "Kconfig recursive dependency limitations"
+
+Kconfig:59:error: recursive dependency detected!
+Kconfig:59:	symbol G depends on G
+For a resolution refer to Documentation/kbuild/kconfig-language.txt
+subsection "Kconfig recursive dependency limitations"
+
+Kconfig:50:error: recursive dependency detected!
+Kconfig:50:	symbol F2 depends on F1
+Kconfig:48:	symbol F1 default value contains F2