An OpenJDK 11u build configured with:

--with-vendor-bug-url='foo&bar&baz' or
--with-vendor-vm-bug-url='foo&bar&baz'

results in this replacement in VersionProps.java in the generated sources:

$ grep VENDOR_URL_BUG build/linux-x86_64-normal-server-release/support/gensrc/java.base/java/lang/VersionProps.java
    private static String VENDOR_URL_BUG =
"foo@@VENDOR_URL_BUG@@bar@@VENDOR_URL_BUG@@baz";
        System.setProperty("java.vendor.url.bug", VENDOR_URL_BUG);

That in turn, results in this strange bug reporting url to show up in hs_err.log files:

#
# A fatal error has been detected by the Java Runtime Environment:
#
# Internal Error (debug.cpp:338), pid=243544, tid=243545
# fatal error: OutOfMemory encountered: Requested array size exceeds VM limit
#
# JRE version: OpenJDK Runtime Environment (11.0.9) (build 11.0.9-internal+0-adhoc.sgehwolf.openjdk-11-dev)
# Java VM: OpenJDK 64-Bit Server VM (11.0.9-internal+0-adhoc.sgehwolf.openjdk-11-dev, mixed mode, tiered, compressed oops, g1 gc, linux-amd64)
# Core dump will be written. Default location: Core dumps may be processed with "/usr/lib/systemd/systemd-coredump %P %u %g %s %t %c %h" (or dumping to /disk/openjdk/upstream-sources/openjdk-11-dev/core.243544)
#
# An error report file with more information is saved as:
# /disk/openjdk/upstream-sources/openjdk-11-dev/hs_err_pid243544.log
#
# If you would like to submit a bug report, please visit:
# foo@@VENDOR_URL_VM_BUG@@bar@@VENDOR_URL_VM_BUG@@baz