Build: Support macOS Armv8/x86-64 univ. binaries

- Rename IOS_ARMV8_BUILD to ARMV8_BUILD.
- Rename install_ios() to install_subbuild() in makemacpkg.
- Wordsmith the build instructions accordingly.
- Use xcode12.2 image in Travis CI.

.travis.yml

@@ -14,7 +14,7 @@ matrix:
         - docker
     - os: osx
       env: BUILD_OFFICIAL=1
-      osx_image: xcode8.3
+      osx_image: xcode12.2
     - os: linux
       compiler: clang
       env:
@@ -72,14 +72,13 @@ before_install:
       sudo apt -y --install-recommends install libc6-dev-x32;
     fi
   - if [ "$TRAVIS_OS_NAME" = "osx" ]; then
-      pushd $HOME/Downloads &&
-      curl -LO https://distfiles.macports.org/MacPorts/MacPorts-2.6.4-10.12-Sierra.pkg &&
-      sudo installer -pkg MacPorts-2.6.4-10.12-Sierra.pkg -target / &&
-      rm MacPorts-2.6.4-10.12-Sierra.pkg &&
+      curl -LO https://distfiles.macports.org/MacPorts/MacPorts-2.6.4-10.15-Catalina.pkg &&
+      sudo installer -pkg MacPorts-2.6.4-10.15-Catalina.pkg -target / &&
+      rm MacPorts-2.6.4-10.15-Catalina.pkg &&
       sudo /opt/local/bin/port -N install yasm md5sha1sum &&
       export PATH=/opt/local/bin:$PATH &&
-      popd &&
       ln -fs /Applications/Xcode.app /Applications/Xcode83.app;
+      ln -fs /Applications/Xcode.app /Applications/Xcode122.app;
     fi
   - if [ "${BUILD_OFFICIAL:-}" != "" ]; then
       if [ "$TRAVIS_OS_NAME" = "linux" ]; then

BUILDING.md

@@ -642,17 +642,18 @@ are installed by default on OS X/macOS 10.7 and later.
 In order to create a Mac package/disk image that contains universal
 x86-64/Arm binaries, set the following CMake variable:
 
-* `IOS_ARMV8_BUILD`: Directory containing an Armv8 (64-bit) iOS build of
+* `ARMV8_BUILD`: Directory containing an Armv8 (64-bit) iOS or macOS build of
   libjpeg-turbo to include in the universal binaries
 
 You should first use CMake to configure an Armv8 sub-build of libjpeg-turbo
-(see "Building libjpeg-turbo for iOS" above) in a build directory that matches
-the one specified in the aforementioned CMake variable.  Next, configure the
-primary (x86-64) build of libjpeg-turbo as an out-of-tree build, specifying the
-aforementioned CMake variable, and build it.  Once the primary build has been
-built, run `make dmg` from the build directory.  The packaging system will
-build the sub-build, use lipo to combine it with the primary build into a
-single set of universal binaries, then package the universal binaries.
+(see "Building libjpeg-turbo for iOS" above, if applicable) in a build
+directory that matches the one specified in the aforementioned CMake variable.
+Next, configure the primary (x86-64) build of libjpeg-turbo as an out-of-tree
+build, specifying the aforementioned CMake variable, and build it.  Once the
+primary build has been built, run `make dmg` from the build directory.  The
+packaging system will build the sub-build, use lipo to combine it with the
+primary build into a single set of universal binaries, then package the
+universal binaries.
 
 
 Windows

cmakescripts/BuildPackages.cmake

@@ -134,8 +134,8 @@ endif() # WIN32
 
 if(APPLE)
 
-set(IOS_ARMV8_BUILD "" CACHE PATH
-  "Directory containing Armv8 iOS build to include in universal binaries")
+set(ARMV8_BUILD "" CACHE PATH
+  "Directory containing Armv8 iOS or macOS build to include in universal binaries")
 
 set(MACOS_APP_CERT_NAME "" CACHE STRING
   "Name of the Developer ID Application certificate (in the macOS keychain) that should be used to sign the libjpeg-turbo DMG.  Leave this blank to generate an unsigned DMG.")

release/makemacpkg.in

@@ -51,7 +51,7 @@ PKGNAME=@PKGNAME@
 VERSION=@VERSION@
 BUILD=@BUILD@
 SRCDIR=@CMAKE_CURRENT_SOURCE_DIR@
-BUILDDIRARMV8=@IOS_ARMV8_BUILD@
+BUILDDIRARMV8=@ARMV8_BUILD@
 WITH_JAVA=@WITH_JAVA@
 MACOS_APP_CERT_NAME="@MACOS_APP_CERT_NAME@"
 MACOS_INST_CERT_NAME="@MACOS_INST_CERT_NAME@"
@@ -98,7 +98,7 @@ if [ "$PREFIX" = "@CMAKE_INSTALL_DEFAULT_PREFIX@" -a "$DOCDIR" = "@CMAKE_INSTALL
 	ln -fs /Library/Documentation/$PKGNAME $PKGROOT$DOCDIR
 fi
 
-install_ios()
+install_subbuild()
 {
 	BUILDDIR=$1
 	ARCHNAME=$2
@@ -160,7 +160,7 @@ install_ios()
 }
 
 if [ "$BUILDDIRARMV8" != "" ]; then
-	install_ios $BUILDDIRARMV8 Armv8 armv8 arm64
+	install_subbuild $BUILDDIRARMV8 Armv8 armv8 arm64
 fi
 
 install_name_tool -id $LIBDIR/$LIBJPEG_DSO_NAME $PKGROOT/$LIBDIR/$LIBJPEG_DSO_NAME