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"backend error: cannot find symbol" and CompilerBugException on reference to method-object parameter in inline anonymous function passed to superclass parameter

See original GitHub issue

This code:

class Inner(Anything(Integer) arg) {}
class Outer(Anything() arg) extends Inner((num) => arg()) {
}
void temp() { }
void mwe() {
	Outer(temp);
}

when compiled with the command-line tools (“ceylon version 1.3.1 74ea8c7 (Now We Try It My Way)”, installed on Mac OS X Sierra via Homebrew) causes the compiler to error out with a “Ceylon backend error” and throw a CompilerBugException:

source/mwe/callable_constructors.ceylon:2: error: Ceylon backend error: cannot find symbol
class Outer(Anything() arg) extends Inner((num) => arg()) {
                                                   ^
  symbol: method arg()
Note: Created module mwe/0.0.1
ceylon compile: Fatal error: The compiler exited abnormally (4) due to a bug in the compiler.
Please report it:
 https://github.com/ceylon/ceylon/issues/new
Please include:

* the stacktrace printed below
* a description of what you were trying to compile.

Thank you!
com.redhat.ceylon.compiler.CompilerBugException: Bug
	at com.redhat.ceylon.compiler.CeylonCompileTool.handleExitCode(CeylonCompileTool.java:929)
	at com.redhat.ceylon.compiler.CeylonCompileTool.run(CeylonCompileTool.java:911)
	at com.redhat.ceylon.common.tools.CeylonTool.run(CeylonTool.java:547)
	at com.redhat.ceylon.common.tools.CeylonTool.execute(CeylonTool.java:423)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:497)
	at com.redhat.ceylon.launcher.Launcher.runInJava7Checked(Launcher.java:108)
	at com.redhat.ceylon.launcher.Launcher.run(Launcher.java:38)
	at com.redhat.ceylon.launcher.Launcher.run(Launcher.java:31)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:497)
	at com.redhat.ceylon.launcher.Bootstrap.runVersion(Bootstrap.java:162)
	at com.redhat.ceylon.launcher.Bootstrap.runInternal(Bootstrap.java:117)
	at com.redhat.ceylon.launcher.Bootstrap.run(Bootstrap.java:93)
	at com.redhat.ceylon.launcher.Bootstrap.main(Bootstrap.java:85)
Caused by: java.lang.ClassCastException: com.redhat.ceylon.langtools.tools.javac.code.Symbol$ClassSymbol cannot be cast to com.redhat.ceylon.langtools.tools.javac.code.Symbol$MethodSymbol
	at com.redhat.ceylon.langtools.tools.javac.jvm.Gen.visitApply(Gen.java:1847)
	at com.redhat.ceylon.langtools.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1464)
	at com.redhat.ceylon.langtools.tools.javac.jvm.Gen.genExpr(Gen.java:949)
	at com.redhat.ceylon.langtools.tools.javac.jvm.Gen.visitSelect(Gen.java:2345)
	at com.redhat.ceylon.langtools.tools.javac.tree.JCTree$JCFieldAccess.accept(JCTree.java:1896)
	at com.redhat.ceylon.langtools.tools.javac.jvm.Gen.genExpr(Gen.java:949)
	at com.redhat.ceylon.langtools.tools.javac.jvm.Gen.visitApply(Gen.java:1843)
	at com.redhat.ceylon.langtools.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1464)
	at com.redhat.ceylon.langtools.tools.javac.jvm.Gen.genExpr(Gen.java:949)
	at com.redhat.ceylon.langtools.tools.javac.jvm.Gen.visitReturn(Gen.java:1809)
	at com.redhat.ceylon.langtools.tools.javac.tree.JCTree$JCReturn.accept(JCTree.java:1383)
	at com.redhat.ceylon.langtools.tools.javac.jvm.Gen.genDef(Gen.java:739)
	at com.redhat.ceylon.langtools.tools.javac.jvm.Gen.genStat(Gen.java:774)
	at com.redhat.ceylon.langtools.tools.javac.jvm.Gen.genStat(Gen.java:760)
	at com.redhat.ceylon.langtools.tools.javac.jvm.Gen.genStats(Gen.java:811)
	at com.redhat.ceylon.langtools.tools.javac.jvm.Gen.visitBlock(Gen.java:1159)
	at com.redhat.ceylon.langtools.tools.javac.tree.JCTree$JCBlock.accept(JCTree.java:908)
	at com.redhat.ceylon.langtools.tools.javac.jvm.Gen.genDef(Gen.java:739)
	at com.redhat.ceylon.langtools.tools.javac.jvm.Gen.genStat(Gen.java:774)
	at com.redhat.ceylon.langtools.tools.javac.jvm.Gen.genMethod(Gen.java:1033)
	at com.redhat.ceylon.langtools.tools.javac.jvm.Gen.visitMethodDef(Gen.java:996)
	at com.redhat.ceylon.langtools.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:777)
	at com.redhat.ceylon.langtools.tools.javac.jvm.Gen.genDef(Gen.java:739)
	at com.redhat.ceylon.langtools.tools.javac.jvm.Gen.genClass(Gen.java:2461)
	at com.redhat.ceylon.compiler.java.tools.LanguageCompiler.genCodeUnlessError(LanguageCompiler.java:807)
	at com.redhat.ceylon.compiler.java.tools.LanguageCompiler.genCode(LanguageCompiler.java:773)
	at com.redhat.ceylon.langtools.tools.javac.main.JavaCompiler.generate(JavaCompiler.java:1575)
	at com.redhat.ceylon.compiler.java.tools.LanguageCompiler.generate(LanguageCompiler.java:946)
	at com.redhat.ceylon.langtools.tools.javac.main.JavaCompiler.generate(JavaCompiler.java:1539)
	at com.redhat.ceylon.langtools.tools.javac.main.JavaCompiler.compile2(JavaCompiler.java:904)
	at com.redhat.ceylon.langtools.tools.javac.main.JavaCompiler.compile(JavaCompiler.java:862)
	at com.redhat.ceylon.compiler.java.tools.LanguageCompiler.compile(LanguageCompiler.java:272)
	at com.redhat.ceylon.compiler.java.launcher.Main.compile(Main.java:658)
	at com.redhat.ceylon.compiler.java.launcher.Main.compile(Main.java:564)
	at com.redhat.ceylon.compiler.java.launcher.Main.compile(Main.java:556)
	at com.redhat.ceylon.compiler.java.launcher.Main.compile(Main.java:545)
	at com.redhat.ceylon.compiler.CeylonCompileTool.run(CeylonCompileTool.java:910)
	... 17 more

OTOH, neither ceylon compile-js nor the IntelliJ plugin reports any error.