Fix Windows build: exclude CZlib where system zlib is absent#9
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The
build (windows-latest)CI job has been failing (pre-existing — also red on trunk) with:zlib ships with the macOS SDK and the Linux Swift toolchain but not on Windows, so the
CZlibwrapper can't compile there.The
MTHCore → CZlibdependency is now gated with.when(platforms: [.macOS, .linux]). A platform condition is evaluated against the build destination, so this is also correct under cross-compilation — unlike a manifest#if os(Windows), which keys off the host that evaluates the manifest (it would pull CZlib into a cross-compile to Windows, and drop it from a cross-compile from Windows to Linux). On any non-listed destination, CZlib drops out of the build graph and the#if canImport(CZlib)-guarded MCCP compression compiles out; macOS/Linux are unchanged.Manifest only — no source changes.
Note: the sibling
Cmth/CmthColorC-oracle targets still use a host-based#if !os(Windows)block. That has the same host-vs-destination limitation, but those are entangled with their product declarations and are C targets that can't build on Windows at all, so converting them is a separate change; the native Windows CI runner is unaffected.