diff --git a/src/julia.h b/src/julia.h
index b29b5d9794457..a7c26977aa20b 100644
--- a/src/julia.h
+++ b/src/julia.h
@@ -2424,19 +2424,24 @@ typedef struct {
 } jl_uv_file_t;
 
 #ifdef __GNUC__
-#define _JL_FORMAT_ATTR(type, str, arg) \
-    __attribute__((format(type, str, arg)))
+#  ifdef __MINGW32__
+#define _JL_FORMAT_ATTR(str, arg) \
+    __attribute__((format(__MINGW_PRINTF_FORMAT, str, arg)))
+#  else
+#define _JL_FORMAT_ATTR(str, arg) \
+    __attribute__((format(printf, str, arg)))
+#  endif
 #else
-#define _JL_FORMAT_ATTR(type, str, arg)
+#define _JL_FORMAT_ATTR(str, arg)
 #endif
 
 JL_DLLEXPORT void jl_uv_puts(struct uv_stream_s *stream, const char *str, size_t n);
 JL_DLLEXPORT int jl_printf(struct uv_stream_s *s, const char *format, ...)
-    _JL_FORMAT_ATTR(printf, 2, 3);
+    _JL_FORMAT_ATTR(2, 3);
 JL_DLLEXPORT int jl_vprintf(struct uv_stream_s *s, const char *format, va_list args)
-    _JL_FORMAT_ATTR(printf, 2, 0);
+    _JL_FORMAT_ATTR(2, 0);
 JL_DLLEXPORT void jl_safe_printf(const char *str, ...) JL_NOTSAFEPOINT
-    _JL_FORMAT_ATTR(printf, 1, 2);
+    _JL_FORMAT_ATTR(1, 2);
 
 extern JL_DLLEXPORT JL_STREAM *JL_STDIN;
 extern JL_DLLEXPORT JL_STREAM *JL_STDOUT;
diff --git a/src/signals-win.c b/src/signals-win.c
index aca20a45dd2ce..4c31df766f3f1 100644
--- a/src/signals-win.c
+++ b/src/signals-win.c
@@ -327,7 +327,7 @@ LONG WINAPI jl_exception_handler(struct _EXCEPTION_POINTERS *ExceptionInfo)
     default:
         jl_safe_printf("UNKNOWN"); break;
     }
-    jl_safe_printf(" at 0x%Ix -- ", (size_t)ExceptionInfo->ExceptionRecord->ExceptionAddress);
+    jl_safe_printf(" at 0x%zx -- ", (size_t)ExceptionInfo->ExceptionRecord->ExceptionAddress);
     jl_print_native_codeloc((uintptr_t)ExceptionInfo->ExceptionRecord->ExceptionAddress);
 
     jl_critical_error(0, 0, ExceptionInfo->ContextRecord, ct);
diff --git a/src/support/utf8.c b/src/support/utf8.c
index 02f541492b0f0..46a6515e9b753 100644
--- a/src/support/utf8.c
+++ b/src/support/utf8.c
@@ -27,7 +27,6 @@
 
 #ifdef _OS_WINDOWS_
 #include <malloc.h>
-#define snprintf _snprintf
 #else
 #if !defined(__FreeBSD__) && !defined(__OpenBSD__)
 #include <alloca.h>