On Thu, 28 Sep 2023 13:13:31 GMT, Maurizio Cimadamore <mcimadam...@openjdk.org> wrote:
> 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) make/modules/java.base/Java.gmk line 26: > 24: # > 25: > 26: DISABLED_WARNINGS_java += this-escape restricted I've disabled restricted warnings in java.base as there's a lot of restricted calls in the Linker API implementation :-) make/test/BuildMicrobenchmark.gmk line 94: > 92: SMALL_JAVA := false, \ > 93: CLASSPATH := $(MICROBENCHMARK_CLASSPATH), \ > 94: DISABLED_WARNINGS := restricted this-escape processing rawtypes cast > serial preview, \ This is needed so that we can compile FFM API benchmarks. test/langtools/tools/javac/diags/examples.not-yet.txt line 219: > 217: compiler.err.annotation.unrecognized.attribute.name > 218: > 219: # this one is transitional (waiting for FFM API to exit preview) Note: in principle I could have added an example for this diagnostic. In practice, the fact that FFM is still a preview API makes this a bit difficult - because we need the sample to also have enable preview flags, and also to catch a bunch of preview diagnostics (some of which I can't add directly as they are also excluded on this file). Since this PR already adds a test, I opted to exclude the diagnostic sample for now, and I will come back later (after FFM is no longer preview) to add one (so as to minimize disruption). ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/15964#discussion_r1340137452 PR Review Comment: https://git.openjdk.org/jdk/pull/15964#discussion_r1340137937 PR Review Comment: https://git.openjdk.org/jdk/pull/15964#discussion_r1340142294
