* I believe that LLVM MemoryBuffer interface is supposed to be read-only
and it's allowed to use eg. read-only mmap of the underlying file.
It isn't appropriate to modify the view at all.
* in case of WASM_ENABLE_DEBUG_AOT, the whole buffer is written as the text
section of the aot file. the modified e_type would confuse dwarf consumers.
note that, even when we are using XIP, the debug info usually contains
relocations. for example, llvm-dwarfdump doesn't seem to perform relocations
on .debug_info section for ET_CORE (== 4 == our E_TYPE_XIP) objects.
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