Avoid spurious test failures when -fno-inline in test flags

These tests rely on inlining, so if -fno-inline is added to the compiler
flags the tests fail. Use the predefined __NO_INLINE__ macro to detect
that situation, and don't bother testing the move assignment.

	* testsuite/21_strings/basic_string/modifiers/assign/char/
	move_assign_optim.cc: Avoid spurious failure when -fno-inline added
	to test flags.
	* testsuite/21_strings/basic_string/modifiers/assign/wchar_t/
	move_assign_optim.cc: Likewise.

From-SVN: r267573

libstdc++-v3/ChangeLog

@@ -1,3 +1,11 @@
+2019-01-04  Jonathan Wakely  <jwakely@redhat.com>
+
+	* testsuite/21_strings/basic_string/modifiers/assign/char/
+	move_assign_optim.cc: Avoid spurious failure when -fno-inline added
+	to test flags.
+	* testsuite/21_strings/basic_string/modifiers/assign/wchar_t/
+	move_assign_optim.cc: Likewise.
+
 2019-01-03  Jonathan Wakely  <jwakely@redhat.com>
 	    Jakub Jelinek  <jakub@redhat.com>
 

libstdc++-v3/testsuite/21_strings/basic_string/modifiers/assign/char/move_assign_optim.cc

@@ -30,6 +30,8 @@ test01(std::string& target, std::string&& source)
   // The move assignment operator should be simple enough that the compiler
   // can see that it never results in a length_error or bad_alloc exception
   // (which would be turned into std::terminate by the noexcept on the
-  // assignment operator).
+  // assignment operator). This is only true when inlining though.
+#ifndef __NO_INLINE__
   target = std::move(source);
+#endif
 }

libstdc++-v3/testsuite/21_strings/basic_string/modifiers/assign/wchar_t/move_assign_optim.cc

@@ -30,6 +30,8 @@ test01(std::wstring& target, std::wstring&& source)
   // The move assignment operator should be simple enough that the compiler
   // can see that it never results in a length_error or bad_alloc exception
   // (which would be turned into std::terminate by the noexcept on the
-  // assignment operator).
+  // assignment operator). This is only true when inlining though.
+#ifndef __NO_INLINE__
   target = std::move(source);
+#endif
 }