I'm using vtune amplifier 2018 for profiling '_int_malloc' in the 'malloc.c'. However, after getting the advanced hot-spots results, when I want to open the function and see the detailed hotspot info about '_int_malloc', vtune complains about not finding the malloc.c source file (see the image below).
According to the picture, VTune was able to read debugging information for your binary module so #2 is not needed. But it looks like the source code you downloaded doesn't match the glibc version used on your system. You can manually recheck it with addr2line Linux utility: addr2line -e <binary_file_path> and then type in any address from the VTune Assembly view ('Address' column) to make sure the source line number reported by addr2line is the same as the source line in VTune views ('Source Line' column). If addr2line and VTune source line numbers are the same, I would suggest double checking versions of glibc binary code and source files.