https://medium.com/graalvm/introducing-the-tracing-agent-simplifying-graalvm-native-image-configuration-c3b56c486271

oh, that is awesome. Will test if that helps with my Immutant Voyage

Hi, I'm tyring to use native-image with specter and it sometimes works -- I ran into this issue: https://github.com/nathanmarz/specter/issues/271 when using a path that's not known at compile time. I've tried select* but apparently that's not good enough I've put the code up here: https://github.com/latacora/casper The exception looks like it's hitting from closed-code:

Exception in thread "main" com.oracle.svm.core.jdk.UnsupportedFeatureError: Unsupported method java.lang.ClassLoader.defineClass(String, byte[], int, int) is reachable: The declaring class of this element has been substituted, but this element is not present in the substitution class, compiling:(NO_SOURCE_PATH:0:0)
	at clojure.lang.Compiler.analyzeSeq(Compiler.java:7010)
	at clojure.lang.Compiler.analyze(Compiler.java:6773)
	at clojure.lang.Compiler.analyzeSeq(Compiler.java:6991)
	at clojure.lang.Compiler.analyze(Compiler.java:6773)
	at clojure.lang.Compiler.analyze(Compiler.java:6729)
	at clojure.lang.Compiler$BodyExpr$Parser.parse(Compiler.java:6100)
	at clojure.lang.Compiler$LetExpr$Parser.parse(Compiler.java:6420)
	at clojure.lang.Compiler.analyzeSeq(Compiler.java:7003)
	at clojure.lang.Compiler.analyze(Compiler.java:6773)
	at clojure.lang.Compiler.analyze(Compiler.java:6729)
	at clojure.lang.Compiler$BodyExpr$Parser.parse(Compiler.java:6100)
	at clojure.lang.Compiler$FnMethod.parse(Compiler.java:5460)
	at clojure.lang.Compiler$FnExpr.parse(Compiler.java:4022)
	at clojure.lang.Compiler.analyzeSeq(Compiler.java:7001)
	at clojure.lang.Compiler.analyze(Compiler.java:6773)
	at clojure.lang.Compiler.eval(Compiler.java:7059)
	at clojure.lang.Compiler.eval(Compiler.java:7025)
	at clojure.core$eval.invokeStatic(core.clj:3206)
	at com.rpl.specter.impl$closed_code.invokeStatic(impl.cljc:617)
	at com.rpl.specter.impl$fn__2322$eval_PLUS___2330.invoke(impl.cljc:636)
	at com.rpl.specter.impl$mk_dynamic_path_maker.invokeStatic(impl.cljc:915)
	at com.rpl.specter.impl$magic_precompilation.invokeStatic(impl.cljc:949)
	at latacora.casper$_main.invokeStatic(casper.clj:14)
	at latacora.casper$_main.doInvoke(casper.clj:8)
	at clojure.lang.RestFn.invoke(RestFn.java:410)
	at clojure.lang.AFn.applyToHelper(AFn.java:154)
	at clojure.lang.RestFn.applyTo(RestFn.java:132)
	at latacora.casper.main(Unknown Source)
Caused by: com.oracle.svm.core.jdk.UnsupportedFeatureError: Unsupported method java.lang.ClassLoader.defineClass(String, byte[], int, int) is reachable: The declaring class of this element has been substituted, but this element is not present in the substitution class
	at com.oracle.svm.core.util.VMError.unsupportedFeature(VMError.java:102)
	at java.lang.ClassLoader.defineClass(Target_java_lang_ClassLoader.java:642)
	at clojure.lang.DynamicClassLoader.defineClass(DynamicClassLoader.java:46)
	at clojure.lang.Compiler$ObjExpr.getCompiledClass(Compiler.java:4979)
	at clojure.lang.Compiler$FnExpr.parse(Compiler.java:4109)
	at clojure.lang.Compiler.analyzeSeq(Compiler.java:7001)
	... 27 more

(def INDEXED
  "A path that visits v and collects k in [[k v], ...].

  This is useful if you want to collect a path to something, see [[path-walker]]
  and [[path-finder]]. "
  [sr/ALL (sr/collect-one sr/FIRST) sr/LAST])

(def INDEXED-SEQ
  "A selector that visits all elements of a seq, and collects their indices.

  This is useful if you want to collect a path to something, see [[path-walker]]
  and [[path-finder]]."
  [(sr/view #(map-indexed vector %)) INDEXED])

(def path-finder
  "Finds the first entry matching `pred` in a deeply nested structure of maps
  and vectors, and collects the path on the way there."
  (sr/recursive-path
   [term-pred] p
   (sr/cond-path
    (sr/pred term-pred) sr/STAY
    map? [INDEXED p]
    coll? [INDEXED-SEQ p])))

I guess the real question is how to avoid that eval; FWIW I tried the native-image tracing tool linked earlier and setting it up was easy but that just gets me to:

com.oracle.svm.core.util.UserError$UserException: Error parsing reflection configuration in file:/home/lvh/src/Latacora/casper/resources/META-INF/native-image/reflect-config.json:
Class cheshire.core$eval1001 not found

of course that doesn't work, that class doesn't "exist yet" 🙂

I have yet to try out that tracing tool. Maybe it’s also something @taylor would like to incorporate in his tools?

I just ran:

#!/usr/bin/env bash
set -Exeou pipefail
CFG_DIR="resources/META-INF/native-image/"
mkdir -p "${CFG_DIR}"
JAVA_HOME="${GRAALVM_HOME}" PATH="${GRAALVM_HOME}/bin:${PATH}" \
         clj \
         -J-agentlib:native-image-agent=config-merge-dir="${CFG_DIR}" \
         $@

you want resources/, not classes/ because something, possibly @taylor's thing, cleaned out classes and then compiled it again

this conveniently got rid of META-INF so the generated config did not get picked up

I saw the profiling thing earlier today and hope to have time to at least add some examples of how to use it

i just always use config-merge-dir, I don't understand why the other option exists

if you don't have config files yet it'll warn

if you really want fresh files, just delete the directory