libs/core/coroutines/CMakeLists.txt                |  1 +
 .../hpx/coroutines/detail/context_posix.hpp        | 17 ++++++++---------
 libs/core/coroutines/src/detail/context_posix.cpp  | 22 ++++++++++++++++++++++
 3 files changed, 31 insertions(+), 9 deletions(-)

diff --git a/libs/core/coroutines/CMakeLists.txt b/libs/core/coroutines/CMakeLists.txt
index 06c6dde6b53..210821b9581 100644
--- a/libs/core/coroutines/CMakeLists.txt
+++ b/libs/core/coroutines/CMakeLists.txt
@@ -52,6 +52,7 @@ set(coroutines_compat_headers
 
 set(coroutines_sources
     detail/context_base.cpp
+    detail/context_posix.cpp
     detail/coroutine_impl.cpp
     detail/coroutine_self.cpp
     detail/posix_utility.cpp
diff --git a/libs/core/coroutines/include/hpx/coroutines/detail/context_posix.hpp b/libs/core/coroutines/include/hpx/coroutines/detail/context_posix.hpp
index 405722e2dba..5c27bfc67f5 100644
--- a/libs/core/coroutines/include/hpx/coroutines/detail/context_posix.hpp
+++ b/libs/core/coroutines/include/hpx/coroutines/detail/context_posix.hpp
@@ -65,6 +65,7 @@
 #include <cstdint>
 #include <exception>
 #include <limits>
+
 #include "pth/pth.h"
 
 namespace hpx { namespace threads { namespace coroutines { namespace detail {
@@ -96,7 +97,7 @@ namespace hpx { namespace threads { namespace coroutines { namespace detail {
         hpx::threads::coroutines::detail::posix::pth::check_(                  \
             pth_uctx_destroy(ctx))
 
-#else                 // generic Posix platform (e.g. OS X >= 10.5)
+#else    // generic Posix platform (e.g. OS X >= 10.5)
 
 /*
  * makecontext based context implementation. Should be available on all
@@ -184,6 +185,10 @@ namespace hpx { namespace threads { namespace coroutines {
         class ucontext_context_impl_base : detail::context_impl_base
         {
         public:
+            // on some platforms SIGSTKSZ resolves to a syscall, we can't make
+            // this constexpr
+            HPX_CORE_EXPORT static std::ptrdiff_t default_stack_size;
+
             ucontext_context_impl_base()
             {
                 HPX_COROUTINE_CREATE_CONTEXT(m_ctx);
@@ -219,19 +224,13 @@ namespace hpx { namespace threads { namespace coroutines {
         public:
             typedef ucontext_context_impl_base context_impl_base;
 
-            enum
-            {
-                default_stack_size = SIGSTKSZ
-            };
-
             /**
              * Create a context that on restore invokes Functor on
              *  a new stack. The stack size can be optionally specified.
              */
             explicit ucontext_context_impl(std::ptrdiff_t stack_size = -1)
-              : m_stack_size(stack_size == -1 ?
-                        static_cast<std::ptrdiff_t>(default_stack_size) :
-                        stack_size)
+              : m_stack_size(
+                    stack_size == -1 ? this->default_stack_size : stack_size)
               , m_stack(nullptr)
               , funp_(&trampoline<CoroutineImpl>)
             {
diff --git a/libs/core/coroutines/src/detail/context_posix.cpp b/libs/core/coroutines/src/detail/context_posix.cpp
new file mode 100644
index 00000000000..c0c3ce65091
--- /dev/null
+++ b/libs/core/coroutines/src/detail/context_posix.cpp
@@ -0,0 +1,22 @@
+//  Copyright (c) 2021 Hartmut Kaiser
+//
+//  SPDX-License-Identifier: BSL-1.0
+//  Distributed under the Boost Software License, Version 1.0. (See accompanying
+//  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+
+#include <hpx/config.hpp>
+
+#if defined(_POSIX_VERSION) || defined(__bgq__) || defined(__powerpc__) ||     \
+    defined(__s390x__)
+#include <hpx/coroutines/detail/context_posix.hpp>
+
+#include <cstddef>
+
+namespace hpx { namespace threads { namespace coroutines { namespace detail {
+    namespace posix {
+
+        std::ptrdiff_t ucontext_context_impl_base::default_stack_size =
+            SIGSTKSZ;
+}}}}}    // namespace hpx::threads::coroutines::detail::posix
+
+#endif