[libcxx] [test] Add (void) casts to operator new calls, to suppress warnings generated by [[nodiscard]].

[BillyONeal]

Summary

Add (void) casts to operator new calls, to suppress warnings generated by [[nodiscard]].

This allows these tests to pass when compiled by MSVC++.

[BillyONeal]

As an FYI, I committed this to subversion as r356632 since I haven't figured out the new git world order yet.....

[BillyONeal]

This broke all the build bots, so I reverted the SVN change. I thought the nodiscard-ness was tested elsewhere but I'm not sure about interaction between this and -faligned-allocation.

[BillyONeal]

This didn't work out, we'll just skip the tests for MSVC++ for now.

[ldionne]

In D59621#1439870, @BillyONeal wrote:

This didn't work out, we'll just skip the tests for MSVC++ for now.

I'd like to understand what's breaking on MSVC so we can address the problem properly -- but I won't push if you just want to skip the tests.

test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size.sh.cpp

 
 // REQUIRES: -faligned-allocation
 // RUN: %compile %verify -faligned-allocation
 
 #include <new>
 
 int main ()
 {
-    ::operator new[](4);  // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
+    (void)::operator new[](4);
 }

test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size_align.sh.cpp

 
 // REQUIRES: -faligned-allocation
 // RUN: %compile %verify -faligned-allocation
 
 #include <new>
 
 int main ()
 {
-    ::operator new[](4, std::align_val_t{4});  // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
+    (void)::operator new[](4, std::align_val_t{4});
 }

test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size_align_nothrow.sh.cpp

 
 // REQUIRES: -faligned-allocation
 // RUN: %compile %verify -faligned-allocation
 
 #include <new>
 
 int main ()
 {
-    ::operator new[](4, std::align_val_t{4}, std::nothrow);  // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
+    (void)::operator new[](4, std::align_val_t{4}, std::nothrow);
 }

test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size_nothrow.sh.cpp

 
 // REQUIRES: -faligned-allocation
 // RUN: %compile %verify -faligned-allocation
 
 #include <new>
 
 int main ()
 {
-    ::operator new[](4, std::nothrow);  // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
+    (void)::operator new[](4, std::nothrow);
 }

test/std/language.support/support.dynamic/new.delete/new.delete.single/new_size_align.sh.cpp

 
 // REQUIRES: -faligned-allocation
 // RUN: %compile %verify -faligned-allocation
 
 #include <new>
 
 int main ()
 {
-    ::operator new(4, std::align_val_t{4});  // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
+    (void)::operator new(4, std::align_val_t{4});
 }

test/std/language.support/support.dynamic/new.delete/new.delete.single/new_size_align_nothrow.sh.cpp

 
 // REQUIRES: -faligned-allocation
 // RUN: %compile %verify -faligned-allocation
 
 #include <new>
 
 int main ()
 {
-    ::operator new(4, std::align_val_t{4}, std::nothrow);  // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
+    (void)::operator new(4, std::align_val_t{4}, std::nothrow);
 }