This patch adds a new lint warning category, namely `-Xlint:restricted` to enable warnings on restricted method calls.
The patch is relatively straightforward: javac marks methods that are marked with the `@Restricted` annotation with a corresponding internal flag. This is done both in `Annotate` when compiling JDK from source, and in `ClassReader` when JDK classfiles are read. When calls to methods marked with the special flag are found, a new warning is issued. While there are some similarities between this new warning and the preview API warnings, the compiler does *not* emit a mandatory note when a compilation unit is found to have one or more restricted method calls. In other words, this is just a plain lint warning. The output from javac looks as follows: Foo.java:6: warning: [restricted] MemorySegment.reinterpret(long) is a restricted method. Arena.ofAuto().allocate(10).reinterpret(100); ^ (Restricted methods are unsafe, and, if used incorrectly, they might crash the JVM or result in memory corruption) ------------- Commit messages: - Add tests - Initial push Changes: https://git.openjdk.org/jdk/pull/15964/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=15964&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8316971 Stats: 95 lines in 14 files changed: 92 ins; 0 del; 3 mod Patch: https://git.openjdk.org/jdk/pull/15964.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/15964/head:pull/15964 PR: https://git.openjdk.org/jdk/pull/15964