1 files changed, 2 insertions, 0 deletions
diff --git a/flake.nix b/flake.nix
index 249da2a04..dfb2dc1f8 100644
--- a/flake.nix
+++ b/flake.nix
@@ -588,6 +588,8 @@
             lcovFilter = [ "*/boost/*" "*-tab.*" ];
 
             hardeningDisable = ["fortify"];
+
+            NIX_CFLAGS_COMPILE = "-DCOVERAGE=1";
           };
 
         # API docs for Nix's unstable internal C++ interfaces.