How to configure openJDK11 for build from sources?

I need to cross-compile from sources this OpenJava fork https://gitlab.com/gosjava/11/openjdk/-/tree/master/ - for aarch64-linux-gnu devkit target: For that I installed java 10.0.2 as host JDK then ran "./configure"

└─$ ./configure    
...
configure: Potential Boot JDK found at /home/katya/java is incorrect JDK version (Picked up _JAVA_OPTIONS: -Dawt.useSystemAAFontSettings=on -Dswing.aatext=true); ignoring
configure: (Your Boot JDK version must be one of: 10 11)
checking for javac... /home/katya/java/bin/javac
checking for java... /home/katya/java/bin/java
configure: Found potential Boot JDK using java(c) in PATH
configure: Potential Boot JDK found at /home/katya/java is incorrect JDK version (Picked up _JAVA_OPTIONS: -Dawt.useSystemAAFontSettings=on -Dswing.aatext=true); ignoring
configure: (Your Boot JDK version must be one of: 10 11)
configure: Could not find a valid Boot JDK. You might be able to fix this by running 'sudo apt-get install openjdk-8-jdk'.
configure: This might be fixed by explicitly setting --with-boot-jdk
configure: error: Cannot continue
configure exiting with result code 1

Full log here https://gist.github.com/iva-nova-e-katerina/3061b865beb48dc25594bc360508d6a3 Could you tell me why the configure said that I use wrong JDK?

Solution

That message is being generated by the BOOTJDK_DO_CHECK autoconf macro whose definition is in "jdk11u/make/autoconf/boot-jdk.m4". If you look at the file you will see the following:

      BOOT_JDK_VERSION=`"$BOOT_JDK/bin/java" -version 2>&1 | $HEAD -n 1`

      # Extra M4 quote needed to protect [] in grep expression.
      [FOUND_CORRECT_VERSION=`$ECHO $BOOT_JDK_VERSION \
          | $EGREP "\"(${DEFAULT_ACCEPTABLE_BOOT_VERSIONS// /|})([\.+-].*)?\""`]
      if test "x$FOUND_CORRECT_VERSION" = x; then
        AC_MSG_NOTICE([Potential Boot JDK found at $BOOT_JDK is incorrect
                       JDK version ($BOOT_JDK_VERSION); ignoring])
        AC_MSG_NOTICE([(Your Boot JDK version must be one of:
                       $DEFAULT_ACCEPTABLE_BOOT_VERSIONS)])
        BOOT_JDK_FOUND=no

(I've added a couple of line breaks for readability ...)

If we compare this to the actual error message:

configure: Potential Boot JDK found at /home/katya/java is incorrect JDK version 
(Picked up _JAVA_OPTIONS: -Dawt.useSystemAAFontSettings=on -Dswing.aatext=true); 
ignoring

So ... it looks like:

You have (or something has) set the _JAVA_OPTIONS environment variable in the environment that is in effect when you run configure.
The java command is warning you that _JAVA_OPTIONS are in effect (for security reasons!). Presumably the real version string gets output as the next line.
The macro captures just the first line (head -n 1) ... and then uses the warning message as if it was the real version string.
This bogus version causes the Boot Java version checking logic to fail.

You probably have a valid Boot JDK ... but configure has been confused by the warning message, and thinks that you don't.

Possible solutions:

Just unset _JAVA_OPTIONS. Those options don't look relevant to what you are doing.
If the are relevant to building, unset _JAVA_OPTIONS while you run configure. Then set it again.
If there is some reason why unsetting _JAVA_OPTIONS won't work, you could modify the above ".m4" file to skip the version check. (Ughhh ...)

You can read more about this unwanted (though actually necessary) behavior of _JAVA_OPTIONS in:

Suppressing the "Picked up _JAVA_OPTIONS" message

(And the short answer is "you can't" ... apart from unsetting the environment variable.)