Fix issues with clang and gcc builds

tests/CMakeLists.txt

@@ -229,8 +229,10 @@ function(add_gsl_asm_test name)
     else()
         target_compile_options(${name}_asm_options INTERFACE
             -S
-            -o ${ASM_LOCATION}\\${name}.s
         )
+        set_target_properties(${name}_asm PROPERTIES PREFIX "")
+        set_target_properties(${name}_asm PROPERTIES OUTPUT_NAME "${ASM_LOCATION}/${name}")
+        set_target_properties(${name}_asm PROPERTIES SUFFIX  ".s")    
     endif(MSVC)
 
     target_link_libraries(${name}_asm

tests/span_compile_only.cpp

@@ -37,20 +37,6 @@ struct fail_fast;
 using namespace std;
 using namespace gsl;
 
-namespace
-{
-struct BaseClass
-{
-};
-struct DerivedClass : BaseClass
-{
-};
-struct AddressOverloaded
-{
-    AddressOverloaded operator&() const { return {}; }
-};
-}
-
 GSL_SUPPRESS(con.4) // NO-FORMAT: attribute
 bool foo()
 {