m4: disable gcc8 -Wcast-function-type warnings from -Wextra

The -Wextra flag bundle gained a new warning -Wcast-function-type.
This complains if you cast between two function prototypes where
the number of parameters or their data types are not compatible.
Unfortunately we need such "bad" function casts for our event
callbacks. It is possible to silence the warning by first casting
to the generic "void (*)(void)" function prototype, but that is
rather ugly to add throughout libvirt code.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This commit is contained in:
Daniel P. Berrangé 2018-02-13 16:40:19 +00:00
parent f2f4e96060
commit 9148293018

View File

@ -177,6 +177,8 @@ AC_DEFUN([LIBVIRT_COMPILE_WARNINGS],[
# with gl_MANYWARN_COMPLEMENT
# So we have -W enabled, and then have to explicitly turn off...
wantwarn="$wantwarn -Wno-sign-compare"
# We do "bad" function casts all the time for event callbacks
wantwarn="$wantwarn -Wno-cast-function-type"
# GNULIB expects this to be part of -Wc++-compat, but we turn
# that one off, so we need to manually enable this again