Hi Mr.Sam,
Actually I am using SDL_ttf. When I was looking inside the code.
I have found that in function "SDL_Surface *TTF_RenderUTF8_Blended_Wrapped(TTF_Font *font, const char *text, SDL_Color fg, Uint32 wrapLength)"
It is allocating "str" then allocating "strLines". If "strLines" fails to allocate, error for out of memory is set and returned NULL. But memory allocated for "str" is not freed. There should be code for freeing the memory allocated to "str" in do-while loop where NULL has returned for allocating "strLines"

Current code in SDL2_ttf-2.0.12 version:

SDL_Surface *TTF_RenderUTF8_Blended_Wrapped(TTF_Font *font, const char *text, SDL_Color fg, Uint32 wrapLength)
{
	//some code
	str = SDL_stack_alloc(char, str_len+1);
	//some code
	strLines = (char **)SDL_realloc(strLines, (numLines+1)*sizeof(*strLines));
	if (!strLines) {
		TTF_SetError("Out of memory");
        return(NULL);
    }
	//some code
}

Code with fix:

SDL_Surface *TTF_RenderUTF8_Blended_Wrapped(TTF_Font *font, const char *text, SDL_Color fg, Uint32 wrapLength)
{
	//some code
	str = SDL_stack_alloc(char, str_len+1);
	//some code
	strLines = (char **)SDL_realloc(strLines, (numLines+1)*sizeof(*strLines));
	if (!strLines) {
		TTF_SetError("Out of memory");
		SDL_stack_free(str);
        return(NULL);
    }
	//some code
}


Regards,
Pankaj