gd has had libimagequant support for some time now. libimagequant is in Fedora since F24 for recent pngquant; gd can use this as well by adding BuildRequires: libimagequant-devel.
This one needs investigation as it breaks 1 test gdimagefile/gdnametest.c:122: 255 pixels different on /tmp/gdtest.CrpdIb/img.gif gdimagefile/gdnametest.c:122: 255 pixels different on /tmp/gdtest.CrpdIb/img.GIF FAIL gdimagefile/gdnametest (exit status: 2)
(In reply to Remi Collet from comment #1) > This one needs investigation as it breaks 1 test Only on F26 i686. Other F26 arches pass, and even i686 passes in an F27 or F28 (rawhide) buildroot. While the buildroots use slightly different versions of libimagequant (2.10.1 vs. 2.10.2), the only changes between these two are Rust-related.
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