bmalloc/ProcessCheck.mm implements specific behavior for Mac and iOS ports, which is guarded with BPLATFORM(COCOA). We should not enable BPLATFORM(MAC) or BPLATFORM(IOS) in JSCOnly, then BPLATFORM(COCOA) won't be defined as well, and code path from ProcessCheck.mm will not be taken
Created attachment 337162 [details] Patch
Comment on attachment 337162 [details] Patch r=me
Should fix GTK/macOS too.
Created attachment 337163 [details] Patch
Now it should actually fix GTK/macOS
Comment on attachment 337163 [details] Patch r=me since Mac does not have maintained CMake port right now.
Note that I've defined BPLATFORM_MAC in PlatformMac, so it should not make things worse for Mac/CMake
Committed r230255: <https://trac.webkit.org/changeset/230255>
<rdar://problem/39174671>