The -fstack-protector-strong used in many distributions by default has a
rather drastic slowdown of the fast path in generated _get_type()
functions using G_DEFINE_* macros. The amount can vary by architecture,
GCC version, and compiler flags.
To work around this, and ensure a higher probability that our fast-path
will match what we had previously, we need to break out the slow-path
(registering the type) into a secondary function that is not a candidate
for inlining.
This ensures that the common case (type registered, return the GType id)
is the hot path and handled in the prologue of the generated assembly even
when -fstack-protector-strong is enabled.
https://bugzilla.gnome.org/show_bug.cgi?id=795180
e924f77736