Adding a workaround to gcc to enforce -O2

[John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>]

Hello!

We have a number of important packages failing to build from source on ia64
because they are using the -O3 optimization level which is currently broken
for this target in gcc [1].

Since I don't know when the upstream bug will be fixed, I would suggest patching
gcc on ia64 such that -O3 is always mapped to -O2 and therefore the broken -O3
optimization level is never used.

Any other opinions?

Adrian

> [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85412

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 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer - glaubitz@debian.org
`. `'   Freie Universitaet Berlin - glaubitz@physik.fu-berlin.de
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