Re: CF_CC_ENV_FLAGS breaks ccache build

[Enrico Scholz]

Thomas Dickey <address@hidden> writes:

>> the CF_CC_ENV_FLAGS code in recent snapshots (20160625) breaks builds
>> where CC looks like
>> 
>> | CC="ccache arm-linux-gnueabi-gcc  -march=armv7ve -marm -mfpu=neon-vfpv4  
>> -mfloat-abi=hard ..."
>> 
>> [...]
>>
>> I am in doubt about the usefulness of CF_CC_ENV_FLAGS and I am not sure
>> what you want to get with it.  But at least, I would trigger it only
>> when '-[IDU]' is in CC.
>
> We got to this point because several people put compiler-flags into $CC
> (here's another special case to deal with).

I guess, they are writing these options into $CC because there are too
much broken buildsystems which use $CFLAGS for mandadatory options and
do not allow the user to override it.

I agree that some language related options can cause problems when $CC
is used for other tasks (other languages (where e.g. $CXX would be the
correct choice) or build steps (e.g. $CPP or $LD)).

But CF_CC_ENV_FLAGS in its actual implementation causes much more trouble
than e.g. an -O3 in $CC.


> Further reading:
>
> https://www.gnu.org/prep/standards/html_node/Command-Variables.html

A $CC value of 'ccache some-gcc -march=... -m... --sysroot=...' is
completely fine. The 'some-gcc' tool will not be able to build a simple
program without them and they affect every part of the build process
(preprocessing, compiling + linking).

And piping it through 'ccache' is widely used.


Enrico