Bump libc version requirement to the latest.

Author: dhardy

Cargo.toml

@@ -18,7 +18,8 @@ members = [
 log = { version = "0.4", optional = true }
 
 [target.'cfg(unix)'.dependencies]
-libc = "0.2.27"
+# In general, we need at least 0.2.27. On Solaris, we need some unknown newer version.
+libc = "0.2.50"
 
 [target.'cfg(windows)'.dependencies]
 winapi = { version = "0.3.6", features = ["minwindef", "ntsecapi", "winnt"] }