+diff --git a/source/utils/CarlaShmUtils.hpp b/source/utils/CarlaShmUtils.hpp
+index 71ca6f0f..3ed53159 100644
+--- a/source/utils/CarlaShmUtils.hpp
++++ b/source/utils/CarlaShmUtils.hpp
+@@ -199,7 +199,11 @@ void* carla_shm_map(carla_shm_t& shm, const std::size_t size) noexcept
+
+ void* const ptr(::mmap(nullptr, size, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_LOCKED, shm.fd, 0));
+
+- if (ptr == nullptr)
++ if (ptr == MAP_FAILED) {
++ carla_stderr("mmap failed: %s", std::strerror(errno));
++ return nullptr;
++ }
++ else if (ptr == nullptr)
+ {
+ carla_safe_assert("ptr != nullptr", __FILE__, __LINE__);
+ return nullptr;
+