gdb: wrap mdebug debuginfo reading in ifdefs

This commit aims to allow a user to enable or disable mdebug support at
compilation time. To do that, a new configure option is added, called
--enable-gdb-mdebug-support (and the accompanying --disable version). By
default, support is enabled, and if a user decides to disable support,
the file mdebugread.c won't be compiled in the final binary, and the
macro MDEBUG_FORMAT_AVAILABLE won't be defined.

That macro is used to control the definitions of mdebug reading, either
the actual definition in mdebugread.c, or a static inline version that
only emits the following warning:

> No mdebug support available.

Ideally, we'd like to guard the entirity of mdebugread in the macro, but
the alpha-mdebug-tdep file uses those directly, and I don't think we
should restrict alpha hosts to requiring that debug format compiled in,
nor do I understand the tdep file enough to be comfortable disentangling
the requirements.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>
Approved-By: Andrew Burgess <aburgess@redhat.com>

0 files changed, 0 insertions, 0 deletions