https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93763
--- Comment #11 from David Binderman <dcb314 at hotmail dot com> ---
(In reply to Jakub Jelinek from comment #10)
> Really depends on the original source, but e.g. if the original testcase
> doesn't have any warnings, then it would be better for the reduction script
> to avoid introducing new warnings (so for start don't use -w in there).
Thanks for your advice, but almost all original source code in practice has
warnings.
> And of course, when the testcase is reduced without that, whomever creates a
> patch where it adds those into the testsuite, it should be tested; if one
> tweaks the test after performing a bootstrap/regtest, it might be enough to
> do
> make check-gcc check-c++-all RUNTESTFLAGS="--target_board=unix\{-m32,-m64\}
> dg.exp=pr12345*"
> style testing just to make sure the test actually passes.
I generally find that if the original source code and the reduced source
code and any tweeked reduced source code all don't demonstrate the problem,
then the problem is fixed.
I keep old bug reports and - usually weekly - make sure there is no regression.
A simple shell script and a diff is usually enough.
For the record, here is my latest script to creduce:
(/usr/bin/gcc -c -w bug584.c && /home/dcb/gcc/results/bin/gcc -c -w -O3
bug584.c) 2>&1 | fgrep "internal compiler error: in
propagate_vals_across_arith_jfunc, at ipa-cp.c:2039"
Using -w means I don't have to wade through a lot of text I am not
interested in to find the internal compiler error.
