SysTools.Ar: trim Apple-ranlib wasm member padding - #192
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Apple's ranlib (cctools; the default `ranlib` on darwin, which cabal runs after `ar` on macOS build hosts) pads each archive member's data to an 8-byte boundary with '\n' bytes and counts that padding into the header's size field. Mach-O readers tolerate the trailing bytes, but the JS backend extracts C-bits wasm objects from package archives and hands them to emscripten, where wasm-ld fails with "section too large" on the padding. Recover a wasm member's true length by walking its section table (a 1-byte id plus a ULEB128 length each) and drop the trailing '\n' padding when the payload is a WebAssembly module. Non-wasm members are returned unchanged.
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Apple's ranlib (cctools; the default
ranlibon darwin, which cabal runs afteraron macOS build hosts) pads each archive member's data to an 8-byte boundary with '\n' bytes and counts that padding into the header's size field. Mach-O readers tolerate the trailing bytes, but the JS backend extracts C-bits wasm objects from package archives and hands them to emscripten, where wasm-ld fails with "section too large" on the padding.Recover a wasm member's true length by walking its section table (a 1-byte id plus a ULEB128 length each) and drop the trailing '\n' padding when the payload is a WebAssembly module. Non-wasm members are returned unchanged.