Import Dasynq 2.1.2

The latest version of Dasynq has better NetBSD support and workarounds
for some spurious compiler warnings.

Author: davmac314

dasynq/include/dasynq/config.h

@@ -53,7 +53,7 @@
 // ---------------------------------------------------------------------------------------------------------
 
 #if !defined(DASYNQ_HAVE_KQUEUE)
-#if defined(__OpenBSD__) || defined(__APPLE__) || defined(__FreeBSD__)
+#if defined(__OpenBSD__) || defined(__APPLE__) || defined(__FreeBSD__) || defined(__NetBSD__)
 #define DASYNQ_HAVE_KQUEUE 1
 #endif
 #endif

dasynq/include/dasynq/interrupt.h

@@ -4,7 +4,10 @@
 #include <unistd.h>
 #include <fcntl.h>
 
-#ifdef DASYNQ_HAVE_EVENTFD
+#include <system_error>
+#include <tuple>
+
+#if DASYNQ_HAVE_EVENTFD
 #include <sys/eventfd.h>
 #endif
 
@@ -24,7 +27,7 @@ template <typename Base, typename Mutex = typename Base::mutex_t> class interrup
 template <typename Base> class interrupt_channel<Base, null_mutex> : public Base
 {
     public:
-    void interrupt_wait()
+    void interrupt_wait() noexcept
     {
 
     }
@@ -33,7 +36,7 @@ template <typename Base> class interrupt_channel<Base, null_mutex> : public Base
 template <typename Base, typename Mutex> class interrupt_channel : public Base
 {
 #if !DASYNQ_HAVE_EVENTFD
-    static inline int create_pipe(int filedes[2])
+    static inline int create_pipe(int filedes[2]) noexcept
     {
         return pipe2(filedes, O_CLOEXEC | O_NONBLOCK);
     }
@@ -63,6 +66,9 @@ template <typename Base, typename Mutex> class interrupt_channel : public Base
         pipe_w_fd = pipedes[1];
 #else
         pipe_r_fd = eventfd(0, EFD_CLOEXEC | EFD_NONBLOCK);
+        if (pipe_r_fd == -1) {
+            throw std::system_error(errno, std::system_category());
+        }
 #endif
 
         try {
@@ -106,7 +112,7 @@ template <typename Base, typename Mutex> class interrupt_channel : public Base
         }
     }
 
-    void interrupt_wait()
+    void interrupt_wait() noexcept
     {
 #if !DASYNQ_HAVE_EVENTFD
         char buf[1] = { 0 };

dasynq/include/dasynq/svec.h

@@ -93,9 +93,14 @@ class svector
     bool change_capacity(size_type c)
             noexcept(std::is_nothrow_move_constructible<T>::value || std::is_nothrow_copy_constructible<T>::value)
     {
+        _Pragma ("GCC diagnostic push")
+        _Pragma ("GCC diagnostic ignored \"-Walloc-size-larger-than=\"")
+
         T *new_storage = (T *)(new (std::nothrow) char[c * sizeof(T)]);
         if (new_storage == nullptr) return false;
 
+        _Pragma ("GCC diagnostic pop")
+
         // To transfer, we prefer move unless it is throwing and copy exists
         svec_helper::move_helper<T>::move(array, new_storage, size_v);
 
@@ -223,9 +228,8 @@ class svector
         return std::numeric_limits<size_type>::max() / sizeof(T);
 
         // if we were to support allocators:
-        //size_t max = std::allocator_traits<std::allocator<char>>::max_size(std::allocator<T>());
-        //return max / sizeof(T);
-        //  (but not / sizeof(T) for C++17 apparently)
+        //size_t max = std::allocator_traits<std::allocator<T>>::max_size(std::allocator<T>());
+        //return max;
     }
 
     void reserve(size_t amount)