GCC 8.0.0 Status Report (2018-01-15), Trunk in Regression and Documentation fixes only mode

[Vincent Lefevre]

On 2018-02-06 17:34:23 +0000, Joseph Myers wrote:
> Use -ffp-contract=off to disable all contraction, or -ffp-contract=on to 
> disable it between statements (which currently actually disables all 
> contraction, as the FMA generation doesn't know what was originally a 
> single source expression).  The default in the absence of such -std 
> options is -ffp-contract=fast (allowing contraction including between 
> different statements).

An environment variable to specify default GCC options would be very
useful. It is too easy to forget such an option.

Note: In the long term, -std=c99 or -std=c11 is better, as if one day,
GCC supports the STDC FP_CONTRACT pragma, contraction could be partly
enabled.

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Vincent Lefèvre <vincent@vinc17.net> - Web: <https://www.vinc17.net/>
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