tree 82bc170ff426cd6be68fac654d3919994747e77a
parent 871d132577729b69bf296f9f04735597a6a2f6bd
author Erwin Rol <erwin@erwinrol.com> 1568572394 +0200
committer Maureen Helm <maureen.helm@nxp.com> 1568662464 -0500

spinlock: Make sure C and C++ have the same sizeof(k_spinlock) value

If CONFIG_SMP and SPIN_VALIDATE are both not defined the k_spinlock
struct will have no members. The result is that in C the sizeof
value of struct k_spinlock is 0 and in C++ it is 1.

This size difference causes problems when the k_spinlock
is embedded into another struct like k_msgq, because C and
C++ will have different ideas on the offsets of the members
that come after the k_spinlock member.

To prevent this we add a 1 byte dummy member to k_spinlock
when the user selects C++ support and k_spinlock would
otherwise be empty.

Signed-off-by: Erwin Rol <erwin@erwinrol.com>