Assert that fmt != NULL before calling vsnprintf (#1969)
In the case of Visual Studio 15.6 + Windows SDK 10.0, vsnprintf() with NULL format string appears to corrupt the stack...
diff --git a/imgui.cpp b/imgui.cpp
index f62fc39..f946865 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -1259,6 +1259,7 @@
#ifndef IMGUI_DISABLE_FORMAT_STRING_FUNCTIONS
int ImFormatString(char* buf, size_t buf_size, const char* fmt, ...)
{
+ IM_ASSERT(fmt != NULL);
va_list args;
va_start(args, fmt);
int w = vsnprintf(buf, buf_size, fmt, args);
@@ -1273,6 +1274,7 @@
int ImFormatStringV(char* buf, size_t buf_size, const char* fmt, va_list args)
{
+ IM_ASSERT(fmt != NULL);
int w = vsnprintf(buf, buf_size, fmt, args);
if (buf == NULL)
return w;
