diff --git a/cmake/modules/SwiftConfigureSDK.cmake b/cmake/modules/SwiftConfigureSDK.cmake
index 134a3f37abb55..b1dbea4f99919 100644
--- a/cmake/modules/SwiftConfigureSDK.cmake
+++ b/cmake/modules/SwiftConfigureSDK.cmake
@@ -429,14 +429,14 @@ macro(configure_sdk_unix name architectures)
 
         set(SWIFT_SDK_FREEBSD_ARCH_${arch}_TRIPLE "${arch}-unknown-freebsd${freebsd_system_version}")
       elseif("${prefix}" STREQUAL "OPENBSD")
-        if(NOT arch STREQUAL "amd64")
+        if(NOT arch STREQUAL "x86_64" AND NOT arch STREQUAL "aarch64")
           message(FATAL_ERROR "unsupported arch for OpenBSD: ${arch}")
         endif()
 
         set(openbsd_system_version ${CMAKE_SYSTEM_VERSION})
         message(STATUS "OpenBSD Version: ${openbsd_system_version}")
 
-        set(SWIFT_SDK_OPENBSD_ARCH_amd64_TRIPLE "amd64-unknown-openbsd${openbsd_system_version}")
+        set(SWIFT_SDK_OPENBSD_ARCH_${arch}_TRIPLE "${arch}-unknown-openbsd${openbsd_system_version}")
 
         if(CMAKE_SYSROOT)
           set(SWIFT_SDK_OPENBSD_ARCH_${arch}_PATH "${CMAKE_SYSROOT}${SWIFT_SDK_OPENBSD_ARCH_${arch}_PATH}" CACHE INTERNAL "sysroot path" FORCE)
diff --git a/stdlib/cmake/modules/AddSwiftStdlib.cmake b/stdlib/cmake/modules/AddSwiftStdlib.cmake
index 55f4ac8225e3a..a078854dc95ca 100644
--- a/stdlib/cmake/modules/AddSwiftStdlib.cmake
+++ b/stdlib/cmake/modules/AddSwiftStdlib.cmake
@@ -529,6 +529,7 @@ function(_add_target_variant_link_flags)
     list(APPEND link_libraries "pthread")
   elseif("${LFLAGS_SDK}" STREQUAL "OPENBSD")
     list(APPEND link_libraries "pthread")
+    list(APPEND result "-Wl,-Bsymbolic")
   elseif("${LFLAGS_SDK}" STREQUAL "CYGWIN")
     # No extra libraries required.
   elseif("${LFLAGS_SDK}" STREQUAL "WINDOWS")
diff --git a/stdlib/public/core/CTypes.swift b/stdlib/public/core/CTypes.swift
index 87995bf616d92..628ba99a0312e 100644
--- a/stdlib/public/core/CTypes.swift
+++ b/stdlib/public/core/CTypes.swift
@@ -108,6 +108,8 @@ public typealias CLongDouble = Double
 #elseif os(OpenBSD)
 #if arch(x86_64)
 public typealias CLongDouble = Float80
+#elseif arch(arm64)
+public typealias CLongDouble = Double
 #else
 #error("CLongDouble needs to be defined for this OpenBSD architecture")
 #endif
diff --git a/utils/build-script-impl b/utils/build-script-impl
index ff7abb2c04e99..05d9070cda52e 100755
--- a/utils/build-script-impl
+++ b/utils/build-script-impl
@@ -459,7 +459,8 @@ function verify_host_is_supported() {
     case ${host} in
       freebsd-arm64             \
       | freebsd-x86_64          \
-      | openbsd-amd64           \
+      | openbsd-x86_64          \
+      | openbsd-aarch64         \
       | cygwin-x86_64           \
       | haiku-x86_64            \
       | linux-x86_64            \
diff --git a/utils/swift_build_support/swift_build_support/targets.py b/utils/swift_build_support/swift_build_support/targets.py
index f5a2748914c22..508d6204eaf68 100644
--- a/utils/swift_build_support/swift_build_support/targets.py
+++ b/utils/swift_build_support/swift_build_support/targets.py
@@ -296,7 +296,7 @@ class StdlibDeploymentTarget(object):
         'x86_64',
         'aarch64'])
 
-    OpenBSD = OpenBSDPlatform("openbsd", archs=["amd64"])
+    OpenBSD = OpenBSDPlatform("openbsd", archs=["x86_64", "aarch64"])
 
     Cygwin = Platform("cygwin", archs=["x86_64"])
 
@@ -403,7 +403,9 @@ def host_target():
 
         elif system == 'OpenBSD':
             if machine == 'amd64':
-                return StdlibDeploymentTarget.OpenBSD.amd64
+                return StdlibDeploymentTarget.OpenBSD.x86_64
+            elif machine == 'arm64':
+                return StdlibDeploymentTarget.OpenBSD.aarch64
 
         elif system == 'CYGWIN_NT-10.0':
             if machine == 'x86_64':