There are currently no rules on the placement of "const", but a recent code submission revealed that there is clearly a preference for spaces around it.
checkpatch.pl has no check at all for this; though it does sometimes complain, but only because it erroneously thinks that the "*" (on local variables) is an unary dereference operator, not a pointer type. Current coding style for const pointers-to-pointers: "*const*": 2 occurrences "* const*": 3 "*const *": 182 "* const *": 681 Just const pointers: "*const": 2833 occurrences "* const": 16615 Link: https://lore.kernel.org/r/264fa39d-aed6-4a54-a085-107997078...@roeck-us.net/ Link: https://lore.kernel.org/r/f511170fe61d7e7214a3a062661cf4103980dad6.ca...@perches.com/ Signed-off-by: Max Kellermann <max.kellerm...@ionos.com> --- V1 -> V2: removed "volatile" on gregkh's request. V2 -> V3: moved patch changelog below the "---" line --- Documentation/process/coding-style.rst | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/Documentation/process/coding-style.rst b/Documentation/process/coding-style.rst index 6db37a46d305..71d62d81e506 100644 --- a/Documentation/process/coding-style.rst +++ b/Documentation/process/coding-style.rst @@ -271,6 +271,17 @@ adjacent to the type name. Examples: unsigned long long memparse(char *ptr, char **retptr); char *match_strdup(substring_t *s); +Use space around the ``const`` keyword (except when adjacent to +parentheses). Example: + +.. code-block:: c + + const void *a; + void * const b; + void ** const c; + void * const * const d; + int strcmp(const char *a, const char *b); + Use one space around (on each side of) most binary and ternary operators, such as any of these:: -- 2.39.2
