kconfiglib: Fix preprocessor issue for nested parentheses

Prompted by an upstream bug report. Nothing in Zephyr triggers this at
the moment, but might as well fix it.

Update Kconfiglib to upstream revision 7d05084b7e, to get this commit
in:

    Fix handling of parentheses in macro argument values

    As an oversight, there was no check for nested parentheses in macro
    arguments, making the preprocessor think the call ended after
    'void)' in

        def_bool $(success,echo 'void foo(void) { asm inline (""); }' \
                   | $(CC) -x c - -c -o /dev/null)

    This broke the latest linux-next kernels (with a Kconfig error),
    starting with commit eb111869301e1 ("compiler-types.h: add
    asm_inline definition").

    I remember seeing this when going through the C code, but somehow
    forgot to put it in. Fix it, and clean up _expand_macro() a bit at
    the same time.

Signed-off-by: Ulf Magnusson <[email protected]>

scripts/kconfig/kconfiglib.py

@@ -554,7 +554,7 @@ def my_other_fn(kconf, name, arg_1, arg_2, ...):
 from os.path import dirname, exists, expandvars, islink, join, realpath
 
 
-VERSION = (12, 14, 0)
+VERSION = (12, 14, 1)
 
 
 # File layout:
@@ -2603,10 +2603,9 @@ def _expand_name_iter(self, s, i):
         while 1:
             match = _name_special_search(s, i)
 
-            if match.group() == "$(":
-                s, i = self._expand_macro(s, match.start(), ())
-            else:
+            if match.group() != "$(":
                 return (s, match.start())
+            s, i = self._expand_macro(s, match.start(), ())
 
     def _expand_str(self, s, i):
         # Expands a quoted string starting at index 'i' in 's'. Handles both
@@ -2649,47 +2648,55 @@ def _expand_macro(self, s, i, args):
         # Returns the expanded 's' (including the part before the macro) and
         # the index of the first character after the expanded macro in 's'.
 
-        start = i
+        res = s[:i]
         i += 2  # Skip over "$("
 
-        # Start of current macro argument
-        arg_start = i
-
-        # Arguments of this macro call
-        new_args = []
+        arg_start = i  # Start of current macro argument
+        new_args = []  # Arguments of this macro call
+        nesting = 0  # Current parentheses nesting level
 
         while 1:
             match = _macro_special_search(s, i)
             if not match:
                 self._parse_error("missing end parenthesis in macro expansion")
 
 
-            if match.group() == ")":
+            if match.group() == "(":
+                nesting += 1
+                i = match.end()
+
+            elif match.group() == ")":
+                if nesting:
+                    nesting -= 1
+                    i = match.end()
+                    continue
+
                 # Found the end of the macro
 
                 new_args.append(s[arg_start:match.start()])
 
-                prefix = s[:start]
-
                 # $(1) is replaced by the first argument to the function, etc.,
                 # provided at least that many arguments were passed
 
                 try:
                     # Does the macro look like an integer, with a corresponding
                     # argument? If so, expand it to the value of the argument.
-                    prefix += args[int(new_args[0])]
+                    res += args[int(new_args[0])]
                 except (ValueError, IndexError):
                     # Regular variables are just functions without arguments,
                     # and also go through the function value path
-                    prefix += self._fn_val(new_args)
+                    res += self._fn_val(new_args)
 
-                return (prefix + s[match.end():],
-                        len(prefix))
+                return (res + s[match.end():], len(res))
 
             elif match.group() == ",":
+                i = match.end()
+                if nesting:
+                    continue
+
                 # Found the end of a macro argument
                 new_args.append(s[arg_start:match.start()])
-                arg_start = i = match.end()
+                arg_start = i
 
             else:  # match.group() == "$("
                 # A nested macro call within the macro
@@ -7015,8 +7022,8 @@ def _re_search(regex):
 # variable assignment
 _assignment_rhs_match = _re_match(r"\s*(=|:=|\+=)\s*(.*)")
 
-# Special characters/strings while expanding a macro (')', ',', and '$(')
-_macro_special_search = _re_search(r"\)|,|\$\(")
+# Special characters/strings while expanding a macro ('(', ')', ',', and '$(')
+_macro_special_search = _re_search(r"\(|\)|,|\$\(")
 
 # Special characters/strings while expanding a string (quotes, '\', and '$(')
 _string_special_search = _re_search(r'"|\'|\\|\$\(')