Port a runtime bytecode reader to native EraVM
Libraries that store data in contract bytecode often recover it with EXTCODECOPY. Native ZKsync compilers do not support that operation as a general way to copy another contract’s code into memory.
Locate the data dependency before changing the library
The example tries to copy 32 bytes beginning at offset zero from target. Search the dependency tree for uses that read a data pointer, inspect runtime metadata or reconstruct a deployed program. Compile the exact path with the target native compiler.
assembly { extcodecopy(target, dest, 0, 32) }
If the goal is to read application data, expose that data through a deliberate storage-backed or computed getter. If the goal is off-chain code inspection, use the appropriate node and artifact tooling. A hash of the program cannot be sliced to recover arbitrary code bytes.
Verify the replacement’s semantics
Check permissions, data layout, historical reads and gas cost after changing the data source. Scope this portability check to native EraVM compilation. EVM bytecode running under an enabled interpreter has a different instruction environment. docs.zksync.io ZKsync documentation