diff --git a/include/mbedtls/check_config.h b/include/mbedtls/check_config.h
index be5c548..357307a 100644
--- a/include/mbedtls/check_config.h
+++ b/include/mbedtls/check_config.h
@@ -525,6 +525,20 @@
 #error "MBEDTLS_PLATFORM_SNPRINTF_MACRO and MBEDTLS_PLATFORM_STD_SNPRINTF/MBEDTLS_PLATFORM_SNPRINTF_ALT cannot be defined simultaneously"
 #endif
 
+#if defined(MBEDTLS_PLATFORM_VSNPRINTF_ALT) && !defined(MBEDTLS_PLATFORM_C)
+#error "MBEDTLS_PLATFORM_VSNPRINTF_ALT defined, but not all prerequisites"
+#endif
+
+#if defined(MBEDTLS_PLATFORM_VSNPRINTF_MACRO) && !defined(MBEDTLS_PLATFORM_C)
+#error "MBEDTLS_PLATFORM_VSNPRINTF_MACRO defined, but not all prerequisites"
+#endif
+
+#if defined(MBEDTLS_PLATFORM_VSNPRINTF_MACRO) &&\
+    ( defined(MBEDTLS_PLATFORM_STD_VSNPRINTF) ||\
+        defined(MBEDTLS_PLATFORM_VSNPRINTF_ALT) )
+#error "MBEDTLS_PLATFORM_VSNPRINTF_MACRO and MBEDTLS_PLATFORM_STD_VSNPRINTF/MBEDTLS_PLATFORM_VSNPRINTF_ALT cannot be defined simultaneously"
+#endif
+
 #if defined(MBEDTLS_PLATFORM_STD_MEM_HDR) &&\
     !defined(MBEDTLS_PLATFORM_NO_STD_FUNCTIONS)
 #error "MBEDTLS_PLATFORM_STD_MEM_HDR defined, but not all prerequisites"
diff --git a/tests/scripts/all.sh b/tests/scripts/all.sh
index c0e0d30..6edd934 100755
--- a/tests/scripts/all.sh
+++ b/tests/scripts/all.sh
@@ -2213,6 +2213,7 @@
     scripts/config.py unset MBEDTLS_PLATFORM_NV_SEED_ALT
     scripts/config.py unset MBEDTLS_PLATFORM_PRINTF_ALT
     scripts/config.py unset MBEDTLS_PLATFORM_SNPRINTF_ALT
+    scripts/config.py unset MBEDTLS_PLATFORM_VSNPRINTF_ALT
     scripts/config.py unset MBEDTLS_ENTROPY_NV_SEED
     scripts/config.py unset MBEDTLS_PLATFORM_C
     make CC=gcc CFLAGS='-Werror -O1' all test
@@ -2238,6 +2239,7 @@
     scripts/config.py unset MBEDTLS_PLATFORM_PRINTF_ALT
     scripts/config.py unset MBEDTLS_PLATFORM_FPRINTF_ALT
     scripts/config.py unset MBEDTLS_PLATFORM_SNPRINTF_ALT
+    scripts/config.py unset MBEDTLS_PLATFORM_VSNPRINTF_ALT
     scripts/config.py unset MBEDTLS_PLATFORM_TIME_ALT
     scripts/config.py unset MBEDTLS_PLATFORM_EXIT_ALT
     scripts/config.py unset MBEDTLS_PLATFORM_NV_SEED_ALT