[Bug debug/86964] [7/8 Regression] Too many debug symbols included, especially for extern globals

[patrickdepinguin at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86964

--- Comment #15 from Thomas De Schampheleire <patrickdepinguin at gmail dot com> ---
Created attachment 46361
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=46361&action=edit
Make -feliminate-unused-debug-symbols the default

Attached patch makes -feliminate-unused-debug-symbols the default.

I also updated the documentation (I hope it is correct). Note that I removed
the explicit reference to 'stabs' format, as it seems no longer correct as
DWARF is supported too.

Is this the correct way forward?