kconfig: check for hex and int mismatches

2026-09-17T23:31:00+00:00

Using a numeric option of one type (e.g. 'int') to determine the value of
a different numeric type (e.g. 'hex') currently fails silently in various
ways if attempted, because the underlying string representation is naively
reused.

Example 1:

  config I
    int
    default -1

  config HEX_DEFAULT_INT
    hex
    default I

Here, HEX_DEFAULT_INT actually gets set to '0x-1', which is of course not
a valid hex value.

Example 2:

  config H
    hex
    default A

  config INT_DEFAULT_HEX
    int
    default H

Here, INT_DEFAULT_HEX actually gets set to 'A', without even converting
into the base-10 equivalent of 10. This value, 'A', is otherwise a
rejected int value if entered in the frontend, or read in from an existing
.config file.

These int-hex mismatches currently do not appear anywhere in the tree, so
it is already safe to make these error out.

Assisted-by: LLM
Signed-off-by: Julian Braha 
Reviewed-by: Nicolas Schier 
Link: https://patch.msgid.link/20260915211508.291790-4-julianbraha@gmail.com
Signed-off-by: Nathan Chancellor

linux-toradex.git/scripts/kconfig/tests/err_num_mismatch, branch master

kconfig: check for hex and int mismatches