diff --git a/ChangeLog b/ChangeLog
index 227faed6b..f8dcae521 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,12 @@
 mbed TLS ChangeLog (Sorted per branch, date)
 
+= mbed TLS x.x.x branch released xxxx-xx-xx
+
+Bugfix
+   * Fix compilation error on Mingw32 when `_TRUNCATE` is defined. Use `_TRUNCATE`
+     only if `__MINGW32__` not defined. Fix suggested by Thomas Glanzmann and
+     Nick Wilson on issue #355
+
 = mbed TLS 2.6.0 branch released 2017-08-10
 
 Security
diff --git a/library/debug.c b/library/debug.c
index f9229b360..db3924ac5 100644
--- a/library/debug.c
+++ b/library/debug.c
@@ -91,7 +91,7 @@ void mbedtls_debug_print_msg( const mbedtls_ssl_context *ssl, int level,
 
     va_start( argp, format );
 #if defined(_WIN32)
-#if defined(_TRUNCATE)
+#if defined(_TRUNCATE) && !defined(__MINGW32__)
     ret = _vsnprintf_s( str, DEBUG_BUF_SIZE, _TRUNCATE, format, argp );
 #else
     ret = _vsnprintf( str, DEBUG_BUF_SIZE, format, argp );
diff --git a/library/platform.c b/library/platform.c
index af3b2f15e..68506f544 100644
--- a/library/platform.c
+++ b/library/platform.c
@@ -74,7 +74,7 @@ int mbedtls_platform_win32_snprintf( char *s, size_t n, const char *fmt, ... )
         return( -1 );
 
     va_start( argp, fmt );
-#if defined(_TRUNCATE)
+#if defined(_TRUNCATE) && !defined(__MINGW32__)
     ret = _vsnprintf_s( s, n, _TRUNCATE, fmt, argp );
 #else
     ret = _vsnprintf( s, n, fmt, argp );