Fix compile errors with ubuntu 20.04 (#880)

* Add build for ubuntu 20.04

* Fix ambiguous overload resolution with stream

* Fix warning

* Capture by value

* Format

.github/workflows/ci.yaml

@@ -147,6 +147,7 @@ jobs:
         os:
           - ubuntu-16.04
           - ubuntu-18.04
+          - ubuntu-20.04
         configuration:
           - debug
           - release

src/include/migraphx/matcher.hpp

@@ -626,7 +626,8 @@ auto tree(M main_op, Ms... ms)
             if(idx != leafs.size())
                 return nullopt;
             // Use explicit captures to workaround ICE on gcc
-            bool found = sequence_c<sizeof...(Ms)>([&ms..., &ctx, &leafs](auto... is) {
+            // Capture by value to workaround compile error on gcc 9
+            bool found = sequence_c<sizeof...(Ms)>([ms..., &ctx, &leafs](auto... is) {
                 return fold(lazy_and{})(ctx.lazy_match(ms, leafs[is])...)();
             });
             if(not found)

test/include/test.hpp

@@ -83,8 +83,8 @@ struct function
     }
 };
 
-template <class Iterator>
-inline std::ostream& stream_range(std::ostream& s, Iterator start, Iterator last)
+template <class Stream, class Iterator>
+inline Stream& stream_range(Stream& s, Iterator start, Iterator last)
 {
     if(start != last)
     {
@@ -94,22 +94,15 @@ inline std::ostream& stream_range(std::ostream& s, Iterator start, Iterator last
     return s;
 }
 
-inline std::ostream& operator<<(std::ostream& s, std::nullptr_t)
+template <class Stream>
+inline Stream& operator<<(Stream& s, std::nullptr_t)
 {
     s << "nullptr";
     return s;
 }
 
-template <class T>
-inline std::ostream& operator<<(std::ostream& s, const std::vector<T>& v)
-{
-    s << "{ ";
-    stream_range(s, v.begin(), v.end());
-    s << "}";
-    return s;
-}
-
-inline std::ostream& operator<<(std::ostream& s, const std::vector<bool>& v)
+template <class Stream, class Range>
+inline auto operator<<(Stream& s, const Range& v) -> decltype(stream_range(s, v.begin(), v.end()))
 {
     s << "{ ";
     stream_range(s, v.begin(), v.end());

test/verify/run_verify.cpp

@@ -27,7 +27,7 @@ std::future<typename std::result_of<Function()>::type> detach_async(Function&& f
         std::packaged_task<result_type()> task(std::forward<Function>(f));
         auto fut = task.get_future();
         std::thread(std::move(task)).detach();
-        return std::move(fut);
+        return fut;
     }
     return std::async(std::launch::deferred, std::forward<Function>(f));
 }