diff --git a/cmake/clang_flags.cmake b/cmake/clang_flags.cmake
index 0619545ec..5ff3db11e 100644
--- a/cmake/clang_flags.cmake
+++ b/cmake/clang_flags.cmake
@@ -2,7 +2,8 @@
 # -Wno-c++98-compat               The library targets C++11.
 # -Wno-c++98-compat-pedantic      The library targets C++11.
 # -Wno-deprecated-declarations    The library contains annotations for deprecated functions.
-# -Wno-extra-semi-stmt            The library uses assert which triggers this warning.
+# -Wno-extra-semi-stmt            Vendored Doctest's CAPTURE() macro expands to a
+#                                 statement followed by a semicolon at every call site.
 # -Wno-padded                     We do not care about padding warnings.
 # -Wno-covered-switch-default     All switches list all cases and a default case.
 # -Wno-c2y-extensions             Clang 22.1 diagnoses __COUNTER__ as a C2y extension, also in
diff --git a/tests/src/unit-assert_macro.cpp b/tests/src/unit-assert_macro.cpp
index adedfc934..ab15b8e5f 100644
--- a/tests/src/unit-assert_macro.cpp
+++ b/tests/src/unit-assert_macro.cpp
@@ -18,7 +18,7 @@ DOCTEST_CLANG_SUPPRESS_WARNING("-Wstrict-overflow")
 static int assert_counter;
 
 /// set failure variable to true instead of calling assert(x)
-#define JSON_ASSERT(x) {if (!(x)) ++assert_counter; }
+#define JSON_ASSERT(x) do { if (!(x)) { ++assert_counter; } } while (false)
 
 #include <nlohmann/json.hpp>
 using nlohmann::json;