From 7f2eb09d6e24bdc46a607e743cb84c30e18ffc93 Mon Sep 17 00:00:00 2001 From: DRC Date: Wed, 30 Nov 2022 18:16:14 -0600 Subject: [PATCH] BUILDING.md: Add Arm64 iOS sim build instructions Unfortunately, iOS builds cannot be used with the iOS simulator on Macs with Apple silicon CPUs. Even more unfortunately, universal binaries can only have one slice for each CPU architecture, so it would not be possible to add a dedicated Arm64 iOS simulator slice to the existing libjpeg-turbo iOS binaries. (It would be necessary to release a separate package solely for the iOS simulator.) Because the Arm Neon SIMD extensions for libjpeg-turbo now use compiler intrinsics when building with Xcode, it is easy to build libjpeg-turbo from source when targeting Arm64-based Apple platforms. Thus, for the moment, I have chosen to document how to avoid the pothole rather than to fill it in. --- BUILDING.md | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/BUILDING.md b/BUILDING.md index 762009e3..66d28670 100644 --- a/BUILDING.md +++ b/BUILDING.md @@ -429,6 +429,10 @@ iPhone 5S/iPad Mini 2/iPad Air and newer. [additional CMake flags] {source_directory} make +Replace `iPhoneOS` with `iPhoneSimulator` and `-miphoneos-version-min` with +`-miphonesimulator-version-min` to build libjpeg-turbo for the iOS simulator on +Macs with Apple silicon CPUs. + Building libjpeg-turbo for Android ----------------------------------