diff --git a/stdlib/cmake/modules/AddSwiftStdlib.cmake b/stdlib/cmake/modules/AddSwiftStdlib.cmake
index 7827533f73e64..ff02c2871bd7b 100644
--- a/stdlib/cmake/modules/AddSwiftStdlib.cmake
+++ b/stdlib/cmake/modules/AddSwiftStdlib.cmake
@@ -1399,6 +1399,9 @@ endfunction()
 # SWIFT_MODULE_DEPENDS_FREEBSD
 #   Swift modules this library depends on when built for FreeBSD.
 #
+# SWIFT_MODULE_DEPENDS_OPENBSD
+#   Swift modules this library depends on when built for OpenBSD.
+#
 # SWIFT_MODULE_DEPENDS_LINUX
 #   Swift modules this library depends on when built for Linux.
 #
@@ -1518,6 +1521,7 @@ function(add_swift_target_library name)
         SWIFT_MODULE_DEPENDS
         SWIFT_MODULE_DEPENDS_CYGWIN
         SWIFT_MODULE_DEPENDS_FREEBSD
+        SWIFT_MODULE_DEPENDS_OPENBSD
         SWIFT_MODULE_DEPENDS_HAIKU
         SWIFT_MODULE_DEPENDS_IOS
         SWIFT_MODULE_DEPENDS_LINUX
@@ -1676,6 +1680,9 @@ function(add_swift_target_library name)
     elseif(${sdk} STREQUAL FREEBSD)
       list(APPEND swiftlib_module_depends_flattened
            ${SWIFTLIB_SWIFT_MODULE_DEPENDS_FREEBSD})
+    elseif(${sdk} STREQUAL OPENBSD)
+      list(APPEND swiftlib_module_depends_flattened
+           ${SWIFTLIB_SWIFT_MODULE_DEPENDS_OPENBSD})
     elseif(${sdk} STREQUAL LINUX OR ${sdk} STREQUAL ANDROID)
       list(APPEND swiftlib_module_depends_flattened
            ${SWIFTLIB_SWIFT_MODULE_DEPENDS_LINUX})
diff --git a/stdlib/public/Differentiation/CMakeLists.txt b/stdlib/public/Differentiation/CMakeLists.txt
index 4c5419a398b80..3efc77077de4b 100644
--- a/stdlib/public/Differentiation/CMakeLists.txt
+++ b/stdlib/public/Differentiation/CMakeLists.txt
@@ -28,6 +28,7 @@ add_swift_target_library(swift_Differentiation ${SWIFT_STDLIB_LIBRARY_BUILD_TYPE
   SWIFT_MODULE_DEPENDS_WATCHOS Darwin
   SWIFT_MODULE_DEPENDS_LINUX Glibc
   SWIFT_MODULE_DEPENDS_FREEBSD Glibc
+  SWIFT_MODULE_DEPENDS_OPENBSD Glibc
   SWIFT_MODULE_DEPENDS_CYGWIN Glibc
   SWIFT_MODULE_DEPENDS_HAIKU Glibc
   SWIFT_MODULE_DEPENDS_WINDOWS MSVCRT
diff --git a/stdlib/public/Differentiation/TgmathDerivatives.swift.gyb b/stdlib/public/Differentiation/TgmathDerivatives.swift.gyb
index a6294247ade73..92fde0c6fbfa3 100644
--- a/stdlib/public/Differentiation/TgmathDerivatives.swift.gyb
+++ b/stdlib/public/Differentiation/TgmathDerivatives.swift.gyb
@@ -16,7 +16,7 @@ import Swift
 
 #if os(macOS) || os(iOS) || os(tvOS) || os(watchOS)
   import Darwin.C.tgmath
-#elseif os(Linux) || os(FreeBSD) || os(PS4) || os(Android) || os(Cygwin) || os(Haiku)
+#elseif os(Linux) || os(FreeBSD) || os(OpenBSD) || os(PS4) || os(Android) || os(Cygwin) || os(Haiku)
   import Glibc
 #elseif os(Windows)
   import MSVCRT