diff --git a/src/Crypto/config.h b/src/Crypto/config.h
index 9e9a2527..1b72bb74 100644
--- a/src/Crypto/config.h
+++ b/src/Crypto/config.h
@@ -61,6 +61,8 @@
 	#elif defined(__GNUC__)
 		#define CRYPTOPP_ALIGN_DATA(x) __attribute__((aligned(x)))
 	#else
+		// Note: expands to nothing for the MSVC bootloader build (TC_WINDOWS_BOOT) and for
+		// compilers that are neither MSVC nor GCC/Clang, so alignment is not guaranteed there.
 		#define CRYPTOPP_ALIGN_DATA(x)
 	#endif
 #endif