note: non-constexpr function addTest cannot be used in a constant expression

Author: vinay-deshmukh

libc/test/UnitTest/LibcTest.cpp

@@ -116,17 +116,6 @@ char **envp = nullptr;
 
 using internal::RunContext;
 
-void Test::addTest(Test *T) {
-  if (End == nullptr) {
-    Start = T;
-    End = T;
-    return;
-  }
-
-  End->Next = T;
-  End = T;
-}
-
 int Test::getNumTests() {
   int N = 0;
   for (Test *T = Start; T; T = T->Next, ++N)

libc/test/UnitTest/LibcTest.h

@@ -127,7 +127,18 @@ class Test {
   static int runTests(const TestOptions &Options);
 
 protected:
-  static void addTest(Test *T);
+  constexpr static void *addTest(Test *T) {
+    if (End == nullptr) {
+      Start = T;
+      End = T;
+      // read  of constexpr
+      return nullptr;
+    }
+
+    End->Next = T;
+    End = T;
+    return nullptr;
+  }
 
   // We make use of a template function, with |LHS| and |RHS| as explicit
   // parameters, for enhanced type checking. Other gtest like unittest