custom CFLAGS lead to missing -c [was: -flto -fwhole-program does not work]

[rofl0r]

gcc -flto -fwhole-program -O3 -mxop -DHAVE_CRYPT -DHAVE_DL -funroll-loops DES_fmt.c
/usr/lib64/gcc/x86_64-suse-linux/4.5/../../../../lib64/crt1.o: In function `_start':
/usr/src/packages/BUILD/glibc-2.11.3/csu/../sysdeps/x86_64/elf/start.S:109: undefined reference to `main'
/tmp/ccEc71Xa.o: In function `valid':
DES_fmt.c:(.text+0x1a): undefined reference to `atoi64'
DES_fmt.c:(.text+0x34): undefined reference to `atoi64'
DES_fmt.c:(.text+0x48): undefined reference to `atoi64'
DES_fmt.c:(.text+0x7f): undefined reference to `atoi64'
/tmp/ccEc71Xa.o: In function `get_key':
DES_fmt.c:(.text+0x117): undefined reference to `DES_bs_all'
/tmp/ccEc71Xa.o: In function `cmp_exact':
DES_fmt.c:(.text+0x204): undefined reference to `DES_bs_get_binary'
/tmp/ccEc71Xa.o: In function `salt':
DES_fmt.c:(.text+0x245): undefined reference to `DES_raw_get_salt'
/tmp/ccEc71Xa.o: In function `cmp_exact':
DES_fmt.c:(.text+0x214): undefined reference to `DES_bs_cmp_one'
/tmp/ccEc71Xa.o: In function `cmp_one':
DES_fmt.c:(.text+0x228): undefined reference to `DES_bs_cmp_one'
/tmp/ccEc71Xa.o: In function `set_salt':
DES_fmt.c:(.text+0x234): undefined reference to `DES_bs_set_salt'
/tmp/ccEc71Xa.o: In function `init':
DES_fmt.c:(.text+0x2e8): undefined reference to `DES_bs_init'
/tmp/ccEc71Xa.o:(.data+0x50): undefined reference to `fmt_default_prepare'
/tmp/ccEc71Xa.o:(.data+0x68): undefined reference to `DES_bs_get_binary'
/tmp/ccEc71Xa.o:(.data+0xc0): undefined reference to `DES_bs_set_key'
/tmp/ccEc71Xa.o:(.data+0xd0): undefined reference to `fmt_default_clear_keys'
/tmp/ccEc71Xa.o:(.data+0xd8): undefined reference to `DES_bs_crypt_25'
/tmp/ccEc71Xa.o:(.data+0xe0): undefined reference to `DES_bs_get_hash_0'
/tmp/ccEc71Xa.o:(.data+0xe8): undefined reference to `DES_bs_get_hash_1'
/tmp/ccEc71Xa.o:(.data+0xf0): undefined reference to `DES_bs_get_hash_2'
/tmp/ccEc71Xa.o:(.data+0xf8): undefined reference to `DES_bs_get_hash_3'
/tmp/ccEc71Xa.o:(.data+0x100): undefined reference to `DES_bs_get_hash_4'
/tmp/ccEc71Xa.o:(.data+0x108): undefined reference to `DES_bs_get_hash_5'
/tmp/ccEc71Xa.o:(.data+0x110): undefined reference to `DES_bs_get_hash_6'
/tmp/ccEc71Xa.o:(.data+0x118): undefined reference to `DES_bs_cmp_all'
collect2: ld returned 1 exit status
make[1]: *** [DES_fmt.o] Error 1
make[1]: Leaving directory `/media/3T/git-mirror/JohnTheRipper/src'
make: *** [linux-x86-64-xop] Error 2

invoked make as:

make clean && make CFLAGS="-flto -fwhole-program -O3" linux-x86-64-xop

[rofl0r]

seems the primary bug is that "-c" gets removed from the CFLAGS when the user passes his own set...

[magnumripper]

We have a JOHN_CFLAGS that you can use to add stuff without dropping our usual CFLAGS.

[rofl0r]

yes, however this is unexpected behaviour.
the polite way would be to just accept the user-passed cflags without breaking
kinda like:

STANDARD_CFLAGS= -c -fomit-frame-pointer ...
ALL_CFLAGS = $(STANDARD_CFLAGS) $(CFLAGS) $(JOHN_CFLAGS)
...
target-xxx:
          $(CC) $(ALL_CFLAGS) $@

edit: reversed cflags order so that user supplied flags come last to override opt levels

[magnumripper]

I'm fine with that but we need to discuss it on john-dev because I have no idea about the history of the current behaviour. Actually some comments in params.h (iirc) claim that you can use CFLAGS normally (add to it).

[rofl0r]

the most proper way to handle this specific case though is when $(CC) is always followed by -c in the makefile target.
i.e. not in the CFLAGS

target-xxx:
        $(CC) -c $@ $(CFLAGS)

[magnumripper]

Agreed. We should do that to the bleeding branch. But ideally Solar should do it in core first (or too).

[magnumripper]

This was fixed once we started using AC.