diff --git a/lib/posix/posix.nim b/lib/posix/posix.nim
index a5ee05abbd..0a2211a402 100644
--- a/lib/posix/posix.nim
+++ b/lib/posix/posix.nim
@@ -29,6 +29,9 @@
 
 {.deadCodeElim:on.}
 
+when defined(Posix) and not defined(haiku):
+  {.passl: "-lm".}
+
 from times import TTime
 
 const