"-dP" option does not output RTL & assembly code?

[Jun Koi]

hi,

i am using GCC v5.4 on Ubuntu 16.04, x86-64 edition.

i run "gcc -dp -dP helloworld.c", and expect to get RTL with assembler
output as comment between instructions. to my surprise, there is no
new dump file created, even though the program is successfully
compiled.

my question: why "-dp -dP" does not work? what do i need to do to have
them work as expected?


thanks.
Jun