v0.4.1

• Fix windows build issues.
• Stop using the nonstandard ulong type.
• Fix typo in PECL conflicts section with weakref PECL.
• Change configure flag to enable/disable this extension to --enable-weakreference_bc

v0.4.0

• Fork this from the abandoned "weakref" PECL to provide WeakMap for php 7.0-7.4 and WeakReference for php 7.0-7.3
• Fix compilation errors for WeakMap in php 7.4
• Rename WeakRef to WeakReference to act as a polyfill for WeakReference in php before php 7.4.
• Make WeakReference constructor throw and require the use of WeakReference::create, like php 7.4
• Fix edge cases when destructor of an old value modifies the weakmap during an update.
• Strictly prevent the creation of dynamic properties on a WeakReference.