Index: .travis.yml
==================================================================
--- .travis.yml
+++ .travis.yml
@@ -64,10 +64,45 @@
     - os: osx
       osx_image: xcode7.3
       language: objective-c
 
     # iOS
+    - os: osx
+      osx_image: xcode11.2
+      language: objective-c
+      env:
+        - config=ios
+    - os: osx
+      osx_image: xcode11.1
+      language: objective-c
+      env:
+        - config=ios
+    - os: osx
+      osx_image: xcode11
+      language: objective-c
+      env:
+        - config=ios
+    - os: osx
+      osx_image: xcode10.3
+      language: objective-c
+      env:
+        - config=ios
+    - os: osx
+      osx_image: xcode10.2
+      language: objective-c
+      env:
+        - config=ios
+    - os: osx
+      osx_image: xcode10.1
+      language: objective-c
+      env:
+        - config=ios
+    - os: osx
+      osx_image: xcode10
+      language: objective-c
+      env:
+        - config=ios
     - os: osx
       osx_image: xcode9.4
       language: objective-c
       env:
         - config=ios
@@ -258,17 +293,17 @@
                                      -D_Nonnull=__nonnull
                                      -D_Null_unspecified=__null_unspecified";
             fi;
 
             export IPHONEOS_DEPLOYMENT_TARGET="9.0";
-            clang="clang --sysroot $(xcrun --sdk iphoneos --show-sdk-path)";
+            clang="clang -isysroot $(xcrun --sdk iphoneos --show-sdk-path)";
             export OBJC="$clang -arch armv7 -arch arm64";
             export OBJCPP="$clang -arch armv7 -E";
             build --host=arm-apple-darwin --enable-static;
 
             sysroot="$(xcrun --sdk iphonesimulator --show-sdk-path)";
-            clang="clang --sysroot $sysroot";
+            clang="clang -isysroot $sysroot";
             export OBJC="$clang -arch i386 -arch x86_64";
             export OBJCPP="$clang -arch i386 -E";
             build WRAPPER=true --host=i386-apple-darwin --enable-static;
     fi
 

Index: README.md
==================================================================
--- README.md
+++ README.md
@@ -51,22 +51,22 @@
   When building for macOS or iOS, everything is built as a `.framework` by
   default if `--disable-shared` has not been specified to `configure`.
 
   To build for iOS, use something like this:
 
-    $ clang="clang --sysroot $(xcrun --sdk iphoneos --show-sdk-path)"
+    $ clang="clang -isysroot $(xcrun --sdk iphoneos --show-sdk-path)"
     $ export OBJC="$clang -arch armv7 -arch arm64"
     $ export OBJCPP="$clang -arch armv7 -E"
-    $ export IPHONEOS_DEPLOYMENT_TARGET="10.0"
+    $ export IPHONEOS_DEPLOYMENT_TARGET="9.0"
     $ ./configure --prefix=/usr/local/ios --host=arm-apple-darwin
 
   To build for the iOS simulator, use something like this:
 
-    $ clang="clang --sysroot $(xcrun --sdk iphonesimulator --show-sdk-path)"
+    $ clang="clang -isysroot $(xcrun --sdk iphonesimulator --show-sdk-path)"
     $ export OBJC="$clang -arch i386 -arch x86_64"
     $ export OBJCPP="$clang -arch i386 -E"
-    $ export IPHONEOS_DEPLOYMENT_TARGET="10.0"
+    $ export IPHONEOS_DEPLOYMENT_TARGET="9.0"
     $ ./configure --prefix=/usr/local/iossim --host=i386-apple-darwin
 
 ### Using the macOS or iOS framework in Xcode
 
   To use the macOS framework in Xcode, you need to add the `.framework`s to