VS 2015 fix

Author: chriskohlhoff

.appveyor.yml

@@ -102,6 +102,8 @@ matrix:
       USING_BOOST: 1
     - image: Visual Studio 2015
       MINGW: 1
+    - image: Visual Studio 2017
+      MINGW: 1
     - image: Visual Studio 2017
       SEPARATE_COMPILATION: 1
     - image: Visual Studio 2017

include/asio/inline_or_executor.hpp

@@ -266,15 +266,13 @@ class inline_or_executor
    *     asio::execution::blocking.never); @endcode
    */
   template <typename Property>
-  inline_or_executor<Executor, execution::blocking_t::never_t,
-      InlineExceptionHandling>
-  require(const Property&,
-      constraint_t<
-        is_same<Property, execution::blocking_t::never_t>::value
-      > = 0,
-      constraint_t<
-        can_require<const Executor&, Property>::value
-      > = 0) const noexcept
+  constraint_t<
+      is_same<Property, execution::blocking_t::never_t>::value
+        && can_require<const Executor&, Property>::value,
+      inline_or_executor<Executor, execution::blocking_t::never_t,
+          InlineExceptionHandling>
+    >
+  require(const Property&) const noexcept
   {
     return inline_or_executor<Executor, execution::blocking_t::never_t,
         InlineExceptionHandling>(executor_);
@@ -329,18 +327,16 @@ class inline_or_executor
    *     asio::execution::relationship.continuation); @endcode
    */
   template <typename Property>
-  inline_or_executor<decay_t<require_result_t<const Executor&, Property>>,
-      Blocking, InlineExceptionHandling>
-  require(const Property& p,
-      constraint_t<
-        can_require<const Executor&, Property>::value
-      > = 0,
-      constraint_t<
-        !is_convertible<Property, execution::blocking_t>::value
-      > = 0,
-      constraint_t<
-        !is_convertible<Property, execution::inline_exception_handling_t>::value
-      > = 0) const
+  constraint_t<
+      can_require<const Executor&, Property>::value
+        && !is_convertible<Property,
+          execution::blocking_t>::value
+        && !is_convertible<Property,
+          execution::inline_exception_handling_t>::value,
+      inline_or_executor<decay_t<require_result_t<const Executor&, Property>>,
+          Blocking, InlineExceptionHandling>
+    >
+  require(const Property& p)
     noexcept(is_nothrow_require<const Executor&, Property>::value)
   {
     return inline_or_executor<

src/Makefile.msc

@@ -349,12 +349,15 @@ asio.lib: asio.cpp
 	lib -name:asio.lib asio.obj
 !endif
 
-!ifdef STANDALONE
 all: \
+	tests\unit\inline_or_executor.exe
+
+!ifdef STANDALONE
+xall: \
 	$(CPP11_EXAMPLE_EXES) \
 	$(UNIT_TEST_EXES)
 !else
-all: \
+xall: \
 	$(LATENCY_TEST_EXES) \
 	$(PERFORMANCE_TEST_EXES) \
 	$(CPP11_EXAMPLE_EXES) \