[RFA] PR c++/42634

[Paolo Carlini]

... my apologies if I'm doing something wrong here, I redid my tests two
times, but I'm afraid we have regressions due to the final version of
the patch :( :( Revision 156021 was fine (see testresults) , and indeed,
everything was fine for me earlier today, now, with 156025, I'm seeing this:

FAIL: 20_util/bind/35569.cc (test for excess errors)
FAIL: 20_util/bind/38889.cc (test for excess errors)
FAIL: 20_util/bind/42593.cc (test for excess errors)
FAIL: 20_util/bind/nested.cc (test for excess errors)
WARNING: 20_util/bind/nested.cc compilation failed to produce executable
FAIL: 20_util/bind/placeholders.cc (test for excess errors)
WARNING: 20_util/bind/placeholders.cc compilation failed to produce
executable
FAIL: 20_util/bind/ref2.cc (test for excess errors)
WARNING: 20_util/bind/ref2.cc compilation failed to produce executable

Note - I'm not sure if it's important, maybe there are interactions with
changes which went in later - the patch for 42634 which I had tested
successfully yesterday is the original one-liner, that posted on
gcc-patches by Dodji the first time, only moving around "args =
INNERMOST_TEMPLATE_ARGS (args);", not the final version, slightly more
complex.

Paolo.