Stop using --gc-sections
for Wasm target to protect metadata sections
#5638
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Stop using --gc-sections for Wasm target to protect metadata sections
Motivation:
Now wasm-ld strips data segments referenced through __start/__stop symbols
during GC, and it removes Swift metadata sections like swift5_protocols.
This option has been added in #4135
Modifications:
We should add support for SHF_GNU_RETAIN-like flag for attribute((retain))
to LLVM and wasm-ld.
For now, just disable section GC for Wasm target.
Context
Result:
Swift metadata sections are retained in the final executable in release configuration for Wasm target.
CC: @MaxDesiatov @keith