RFC: run testsuite with -O3

[Andrew Haley]

Jeff Sturm writes:
 > I've been testing gcj with the following in my tree.  From having no
 > regular test coverage for -O3, I found that some regressions had crept
 > into gcj.  Testing regularly with -O3 should prevent that.
 > 
 > The obvious drawback is longer times to run the testsuite.  As a
 > compromise, we could add -O3 to compile.exp only with just a small
 > increase.

Can we not scratch -O?  What good is testing with -O *and* with -O3?

Andrew.