java under Spindle not searching RPATH for libjli

Start by tracing Spindle's dynamic-library loading and RPATH handling; the issue does not name source files or tests, so locate those entry points in the repository first. Reproduce with Java 11 and compare its library search behavior under Spindle with Java 25. Done means Java 11 can resolve libjli.so under Spindle, with relevant regression coverage passing.

The stc test failure in the E4S testsuite is caused by java failing to find a library under Spindle that it can find without Spindle. The stc test depends on an older version of Java (Java 11), for which the problem occurs, but it does not occur with Java 25.

The failure can be reproduced in the serial CI container:

spindleuser@spindlenode:~$ sudo apt install openjdk-11-jre
[...]
spindleuser@spindlenode:~$ sudo apt install openjdk-25-jre
[...]

Java 11 works without Spindle but can't find libjli.so under Spindle:

spindleuser@spindlenode:~$ /usr/lib/jvm/java-11-openjdk-amd64/bin/java -version
openjdk version "11.0.32.1" 2026-08-18
OpenJDK Runtime Environment (build 11.0.32.1+1-post-1ubuntu1-24.04-Ubuntu)
OpenJDK 64-Bit Server VM (build 11.0.32.1+1-post-1ubuntu1-24.04-Ubuntu, mixed mode, sharing)

spindleuser@spindlenode:~$ spindle /usr/lib/jvm/java-11-openjdk-amd64/bin/java -version
java: error while loading shared libraries: libjli.so: cannot open shared object file: No such file or directory

Java 25 works in either case:

spindleuser@spindlenode:~$ /usr/lib/jvm/java-25-openjdk-amd64/bin/java -version
openjdk version "25.0.4.1" 2026-08-18
OpenJDK Runtime Environment (build 25.0.4.1+1-1-24.04.4-Ubuntu)
OpenJDK 64-Bit Server VM (build 25.0.4.1+1-1-24.04.4-Ubuntu, mixed mode, sharing)
spindleuser@spindlenode:~$ spindle /usr/lib/jvm/java-25-openjdk-amd64/bin/java -version
openjdk version "25.0.4.1" 2026-08-18
OpenJDK Runtime Environment (build 25.0.4.1+1-1-24.04.4-Ubuntu)
OpenJDK 64-Bit Server VM (build 25.0.4.1+1-1-24.04.4-Ubuntu, mixed mode, sharing)

Java 11 dynamic section:

spindleuser@spindlenode:~$ readelf -d /usr/lib/jvm/java-11-openjdk-amd64/bin/java

Dynamic section at offset 0x2d40 contains 31 entries:
  Tag        Type                         Name/Value
 0x0000000000000001 (NEEDED)             Shared library: [libz.so.1]
 0x0000000000000001 (NEEDED)             Shared library: [libjli.so]
 0x0000000000000001 (NEEDED)             Shared library: [libc.so.6]
 0x000000000000000f (RPATH)              Library rpath: [$ORIGIN/../lib/jli:$ORIGIN/../lib]
[...]

Java 25 dynamic section:

spindleuser@spindlenode:~$ readelf -d /usr/lib/jvm/java-25-openjdk-amd64/bin/java

Dynamic section at offset 0x2d60 contains 29 entries:
  Tag        Type                         Name/Value
 0x0000000000000001 (NEEDED)             Shared library: [libjli.so]
 0x0000000000000001 (NEEDED)             Shared library: [libc.so.6]
 0x000000000000000f (RPATH)              Library rpath: [$ORIGIN:$ORIGIN/../lib]
[...]

Without Spindle, libjli is found in the first location searched, $ORIGIN/../lib/jli:

  2       2493:     file=libz.so.1 [0];  needed by /usr/lib/jvm/java-11-openjdk-amd64/bin/java [0]
  3       2493:     find library=libz.so.1 [0]; searching
  4       2493:      search path=/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/jli/glibc-hwcaps/x86-64-v3:/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/jli/glibc-hwcaps/x86-64-v2:/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/jli:/usr/lib/jvm/java-11-openj    dk-amd64/bin/../lib/glibc-hwcaps/x86-64-v3:/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/glibc-hwcaps/x86-64-v2:/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib                (RPATH from file /usr/lib/jvm/java-11-openjdk-amd64/bin/java)
  5       2493:       trying file=/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/jli/glibc-hwcaps/x86-64-v3/libz.so.1
  6       2493:       trying file=/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/jli/glibc-hwcaps/x86-64-v2/libz.so.1
  7       2493:       trying file=/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/jli/libz.so.1
  8       2493:       trying file=/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/glibc-hwcaps/x86-64-v3/libz.so.1
  9       2493:       trying file=/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/glibc-hwcaps/x86-64-v2/libz.so.1
 10       2493:       trying file=/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/libz.so.1
 11       2493:      search cache=/etc/ld.so.cache
 12       2493:       trying file=/lib/x86_64-linux-gnu/libz.so.1
 13       2493:
 14       2493:     file=libz.so.1 [0];  generating link map
 15       2493:       dynamic: 0x0000719976091dd0  base: 0x0000719976077000   size: 0x000000000001b098
 16       2493:         entry: 0x0000719976077000  phdr: 0x0000719976077040  phnum:                 11
 17       2493:
 18       2493:
 19       2493:     file=libjli.so [0];  needed by /usr/lib/jvm/java-11-openjdk-amd64/bin/java [0]
 20       2493:     find library=libjli.so [0]; searching
 21       2493:      search path=/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/jli:/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib            (RPATH from file /usr/lib/jvm/java-11-openjdk-amd64/bin/java)
 22       2493:       trying file=/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/jli/libjli.so
 23       2493:
 24       2493:     file=libjli.so [0];  generating link map
 25       2493:       dynamic: 0x0000719976075b28  base: 0x0000719976065000   size: 0x0000000000011120
 26       2493:         entry: 0x0000719976065000  phdr: 0x0000719976065040  phnum:                 11

With Spindle, the executable's RPATH is searched when looking for the first library, libz, but is NOT searched when looking for libjli:

   	   2487:     file=libz.so.1 [0];  needed by /usr/lib/jvm/java-11-openjdk-amd64/bin/java [0]
      2487:     find library=libz.so.1 [0]; searching
      2487:      search path=/tmp/commpath/cachepath/spindle.ebd36db3852edbd0/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/jli/glibc-hwcaps/x86-64-v3:/tmp/commpath/cachepath/spindle.ebd36db3852edbd0/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/jli/glibc-hwcaps/x86-64-v2:/tmp/commpath/cachepath/spindle.ebd36db3852edbd0/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/jli:/tmp/commpath/cachepath/spindle.ebd36db3852edbd0/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/glibc-hwcaps/x86-64-v3:/tmp/commpath/cachepath/spindle.ebd36db3852edbd0/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/glibc-hwcaps/x86-64-v2:/tmp/commpath/cachepath/spindle.ebd36db3852edbd0/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib                (RPATH from file /usr/lib/jvm/java-11-openjdk-amd64/bin/java)
      2487:       trying file=/tmp/commpath/cachepath/spindle.ebd36db3852edbd0/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/jli/glibc-hwcaps/x86-64-v3/libz.so.1
      2487:       trying file=/tmp/commpath/cachepath/spindle.ebd36db3852edbd0/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/jli/glibc-hwcaps/x86-64-v2/libz.so.1
      2487:       trying file=/tmp/commpath/cachepath/spindle.ebd36db3852edbd0/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/jli/libz.so.1
      2487:       trying file=/tmp/commpath/cachepath/spindle.ebd36db3852edbd0/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/glibc-hwcaps/x86-64-v3/libz.so.1
      2487:       trying file=/tmp/commpath/cachepath/spindle.ebd36db3852edbd0/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/glibc-hwcaps/x86-64-v2/libz.so.1
      2487:       trying file=/tmp/commpath/cachepath/spindle.ebd36db3852edbd0/usr/lib/jvm/java-11-openjdk-amd64/bin/../lib/libz.so.1
      2487:      search cache=/etc/ld.so.cache
      2487:       trying file=/lib/x86_64-linux-gnu/libz.so.1
      2487:
      2487:     file=libz.so.1 [0];  generating link map
      2487:       dynamic: 0x00007972581eadd0  base: 0x00007972581d0000   size: 0x000000000001b098
      2487:         entry: 0x00007972581d0000  phdr: 0x00007972581d0040  phnum:                 11
      2487:
      2487:
      2487:     file=libjli.so [0];  needed by /usr/lib/jvm/java-11-openjdk-amd64/bin/java [0]
      2487:     find library=libjli.so [0]; searching
      2487:      search cache=/etc/ld.so.cache
      2487:      search path=/lib/x86_64-linux-gnu:/usr/lib/x86_64-linux-gnu/glibc-hwcaps/x86-64-v3:/usr/lib/x86_64-linux-gnu/glibc-hwcaps/x86-64-v2:/usr/lib/x86_64-linux-gnu:/lib/glibc-hwcaps/x86-64-v3:/lib/glibc-hwcaps/x86-64-v2:/lib:/usr/lib/glibc-hwcaps/x86-64-v3:/usr/lib/glibc-hwcaps/x86-64-v2:/usr/lib            (system search path)
      2487:       trying file=/lib/x86_64-linux-gnu/libjli.so
      2487:       trying file=/usr/lib/x86_64-linux-gnu/glibc-hwcaps/x86-64-v3/libjli.so
      2487:       trying file=/__not_exists/4-linux-gnu/glibc-hwcaps/x86-64-v2/libjli.so
      2487:       trying file=/__not_exists/4-linux-gnu/libjli.so
      2487:       trying file=/lib/glibc-hwcaps/x86-64-v3/libjli.so
      2487:       trying file=/__noglibc-hwcaps/x86-64-v2/libjli.so
      2487:       trying file=/__nolibjli.so
      2487:       trying file=/usr/lib/glibc-hwcaps/x86-64-v3/libjli.so
      2487:       trying file=/__not_exglibc-hwcaps/x86-64-v2/libjli.so
      2487:       trying file=/__not_exlibjli.so
      2487:
/usr/lib/jvm/java-11-openjdk-amd64/bin/java: error while loading shared libraries: libjli.so: cannot open shared object file: No such file or directory

The reason that Java 25 works appears to be that libjli is the first library loaded there. RPATH is being searched for the first library with either Java version.