diff --git a/llvm/utils/gn/secondary/llvm/include/llvm/Config/BUILD.gn b/llvm/utils/gn/secondary/llvm/include/llvm/Config/BUILD.gn
--- a/llvm/utils/gn/secondary/llvm/include/llvm/Config/BUILD.gn
+++ b/llvm/utils/gn/secondary/llvm/include/llvm/Config/BUILD.gn
@@ -89,7 +89,7 @@
     "HAVE_LIBPFM=",
     "HAVE_LIBPSAPI=",
     "HAVE_MALLCTL=",
-    "HAVE_MALLINFO2=",
+    "HAVE_MALLINFO2=1",
     "HAVE_SIGNAL_H=1",
     "HAVE_STD_IS_TRIVIALLY_COPYABLE=1",
     "HAVE_STRERROR=1",