[flang] Disable noalias by default (#142128) With these enabled we see a 70% performance regression for exchange2_r on neoverse-v1 (aws graviton 3) using `-mcpu=native -Ofast -flto`. There is also a smaller regression on neoverse-v2. This appears to be because function specialization is no longer kicking in during LTO for digits_2. This can be seen in the output executable: previously it contained specialized copies of the function with names like `_QMbrute_forcePdigits_2.specialized.4`. Now there are no names like this. The bug is not in flang - instead in the function specialization pass - but due to the size of the regression I would like to request that this is disabled until function specialization has been fixed.
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