readline rebase 5.1->6.2?

[Jan Kratochvil <jan.kratochvil@redhat.com>]

Hi,

it is a bity pity the sourceware tree still bundles readline-5.1 while distros
build GDB with readline less than 5 years old.

This means in practice GDB already runs without the custom patches contained
in src/readline/ , just making GDB forked with individual downstream patch fix
ups of the compatibility.

Just the patches are of the kind of MS-related platforms compatibility:
	+dnl BEGIN changes for CYGNUS cross-building for Cygwin
	+#ifdef __MSDOS__
	+#if defined (__GO32__)
	+#ifndef __MINGW32__
	!+#if defined (SIGWINCH)
	? (+#if defined (HAVE_GETPWENT))

Other patches are for rl_prompt and signals where there were enough upstream
readline modifications I do not think these patches are meaningfully
applicable anymore.

Unfortunately there is AFAIK usually (in some cases there is) no testcase of
readline.

Before 7.3 cut off I ask about the opinion on these MS-related platforms
compatibility readline patches, Fedora GNU/Linux runs fine with
readline-6.1-2.fc14 with readline-6.2-2.fc15 soon to be GA and also no
reported problems.


Thanks,
Jan