--- a/hotspot/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.hotspot/src/org/graalvm/compiler/hotspot/JVMCIVersionCheck.java	Tue Jul 04 15:58:15 2017 +0200
+++ b/hotspot/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.hotspot/src/org/graalvm/compiler/hotspot/JVMCIVersionCheck.java	Tue Jul 04 11:45:09 2017 -0700
@@ -23,6 +23,7 @@
 package org.graalvm.compiler.hotspot;
 
 import java.util.Formatter;
+import java.util.Objects;
 
 /**
  * Mechanism for checking that the current Java runtime environment supports the minimum JVMCI API
@@ -37,10 +38,11 @@
 class JVMCIVersionCheck {
 
     private static final int JVMCI8_MIN_MAJOR_VERSION = 0;
-    private static final int JVMCI8_MIN_MINOR_VERSION = 23;
+    private static final int JVMCI8_MIN_MINOR_VERSION = 26;
 
-    // Will be updated once an ea build with the required JVMCI API is available.
-    private static final int JVMCI9_MIN_EA_BUILD = 143;
+    // MAX_VALUE indicates that no current EA version is compatible with Graal.
+    // Note: Keep README.md in sync with the EA version support checked here.
+    private static final int JVMCI9_MIN_EA_BUILD = 176;
 
     private static void failVersionCheck(boolean exit, String reason, Object... args) {
         Formatter errorMessage = new Formatter().format(reason, args);
@@ -77,13 +79,27 @@
                 start += "-jvmci-".length();
                 int end = vmVersion.indexOf('.', start);
                 if (end > 0) {
-                    int major = Integer.parseInt(vmVersion.substring(start, end));
+                    int major;
+                    try {
+                        major = Integer.parseInt(vmVersion.substring(start, end));
+                    } catch (NumberFormatException e) {
+                        failVersionCheck(exitOnFailure, "The VM does not support the minimum JVMCI API version required by Graal.%n" +
+                                        "Cannot read JVMCI major version from java.vm.version property: %s.%n", vmVersion);
+                        return;
+                    }
                     start = end + 1;
                     end = start;
                     while (end < vmVersion.length() && Character.isDigit(vmVersion.charAt(end))) {
                         end++;
                     }
-                    int minor = Integer.parseInt(vmVersion.substring(start, end));
+                    int minor;
+                    try {
+                        minor = Integer.parseInt(vmVersion.substring(start, end));
+                    } catch (NumberFormatException e) {
+                        failVersionCheck(exitOnFailure, "The VM does not support the minimum JVMCI API version required by Graal.%n" +
+                                        "Cannot read JVMCI minor version from java.vm.version property: %s.%n", vmVersion);
+                        return;
+                    }
                     if (major >= JVMCI8_MIN_MAJOR_VERSION && minor >= JVMCI8_MIN_MINOR_VERSION) {
                         return;
                     }
@@ -96,7 +112,7 @@
                             "Cannot read JVMCI version from java.vm.version property: %s.%n", vmVersion);
         } else {
             if (vmVersion.contains("SNAPSHOT")) {
-                // The snapshot of http://hg.openjdk.java.net/jdk9/hs tip is expected to work
+                // The snapshot of http://hg.openjdk.java.net/jdk9/dev tip is expected to work
                 return;
             }
             if (vmVersion.contains("internal")) {
@@ -104,23 +120,36 @@
                 return;
             }
             // http://openjdk.java.net/jeps/223
-            // Only support EA builds until GA is available
-            if (vmVersion.startsWith("9-ea+")) {
-                int start = "9-ea+".length();
+            if (vmVersion.startsWith("9+")) {
+                int start = "9+".length();
                 int end = start;
                 end = start;
                 while (end < vmVersion.length() && Character.isDigit(vmVersion.charAt(end))) {
                     end++;
                 }
-                int build = Integer.parseInt(vmVersion.substring(start, end));
+                int build;
+                try {
+                    build = Integer.parseInt(vmVersion.substring(start, end));
+                } catch (NumberFormatException e) {
+                    failVersionCheck(exitOnFailure, "The VM does not support the minimum JVMCI API version required by Graal.%n" +
+                                    "Cannot read JDK9 EA build number from java.vm.version property: %s.%n", vmVersion);
+                    return;
+                }
                 if (build >= JVMCI9_MIN_EA_BUILD) {
                     return;
                 }
-                failVersionCheck(exitOnFailure, "The VM is an insufficiently recent EA JDK9 build for Graal: %d < %d.%n", build, JVMCI9_MIN_EA_BUILD);
+                // Using Object.equals suppresses Eclipse's "Dead code" warning.
+                // Unfortunately @SuppressWarnings("unused") can only be applied at method level.
+                if (Objects.equals(JVMCI9_MIN_EA_BUILD, Integer.MAX_VALUE)) {
+                    failVersionCheck(exitOnFailure, "This version of Graal is not compatible with any JDK 9 Early Access build.%n");
+                } else {
+                    failVersionCheck(exitOnFailure, "The VM is an insufficiently recent EA JDK9 build for Graal: %d < %d.%n", build, JVMCI9_MIN_EA_BUILD);
+                }
                 return;
+            } else {
+                // Graal will be compatible with all JDK versions as of 9 GA
+                // until a JVMCI API change is made in a 9u or later release.
             }
-            failVersionCheck(exitOnFailure, "The VM does not support the minimum JVMCI API version required by Graal.%n" +
-                            "Cannot read JDK9 EA build number from java.vm.version property: %s.%n", vmVersion);
         }
     }