<div dir="ltr">Hello! Someone recently tipped me off to using -whole-module-optimization flag with -Onone for use during debug builds to speed up compile times. In our project, the speedup feels quite dramatic, but when it gets to the linking step (after compiling both Swift and Obj-C in the project) it fails because ld can't find the individual object files that normally get emitted during the debug-type build presumably because -whole-module-optimization only emits one (and this isn't a normal "-Owholemodule"-type build which works fine).<div><br></div><div>I can't seem to reproduce this outside of Xcode, but I was curious if anyone has tried this and knows of a workaround to get -whole-module-optimization to work with -Onone in Xcode?</div><div><br></div><div>I'm currently using Xcode 8.1 (App Store build) and Swift 3 on macOS Sierra.</div><div><br></div><div>Thanks!<br clear="all"><div><br></div><div class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr">Ben</div></div></div></div>
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