RFR: 8296010: AssertionError in annotationTargetType

[Vicente Romero]

javac is crashing if a class file is forged so that an annotation can be applicable to an unknown target. It would be equivalent to the following declaration:


@Target(ElementType.NO_SUCH)
@interface A {}

if the compiler process this source it would issue a compiler error, indicating that symbol `NO_SUCH` cant be found. Currently our class reader just issues a warning and move on. This is OK as it could be that the loaded class won't be used anyway but if this annotation is actually applied to symbol as in:


class B {
    @A Object o;
}

then this to my understanding should be a compilation error. Currently javac is crashing and this is not acceptable, so this PR is fixing this issue so that a compilation error is issued instead.

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Commit messages:
 - 8296010: AssertionError in annotationTargetType

Changes: https://git.openjdk.org/jdk/pull/12241/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=12241&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8296010
  Stats: 116 lines in 7 files changed: 98 ins; 1 del; 17 mod
  Patch: https://git.openjdk.org/jdk/pull/12241.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12241/head:pull/12241

PR: https://git.openjdk.org/jdk/pull/12241