JDK-8288850 : SegmentAllocator:allocate() can return null some cases
  • Type: Bug
  • Component: core-libs
  • Sub-Component: java.lang.foreign
  • Affected Version: 19
  • Priority: P3
  • Status: Resolved
  • Resolution: Fixed
  • Submitted: 2022-06-21
  • Updated: 2022-07-27
  • Resolved: 2022-07-12
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JDK 19 JDK 20
19 b31Fixed 20Fixed
Related Reports
Relates :  
JDK-8282192 - Implementation of Foreign Function & Memory API (Preview)
Description
Observed that allocate(bytesSize) and allocate(bytesSize, alignment) might throw OutOfMemoryError when bytesSize is too long.

IMO, this can be stated in spec.

And also observed that allocate(bytesSize, alignment) can return null, with  
====
 SegmentAllocator segmentAllocator = SegmentAllocator.newNativeArena(MemorySession.openConfined());
        MemorySegment memorySegment = segmentAllocator.allocate(Long.MAX_VALUE, 2);
        System.out.println(" The memorySegment is " + memorySegment);
====

If this is a valid case Spec can be enhanced for this.
Comments
Changeset: 2baf526f Author: Maurizio Cimadamore <mcimadamore@openjdk.org> Date: 2022-07-12 14:14:46 +0000 URL: https://git.openjdk.org/jdk19/commit/2baf526fcec3ecd8e306fd9bd483ab5ed4ec8afe
12-07-2022
A pull request was submitted for review. URL: https://git.openjdk.org/jdk19/pull/133 Date: 2022-07-11 15:05:34 +0000
11-07-2022
The lack of OutOfMemoryError is not an issue - this dynamic exception is not specified in other methods as well (see MemorySegment::allocateNative). Other API methods such as ByteBuffer::allocateDirect similarly do not specify this. But the `null` result is something bad which should be fixed.
11-07-2022