Q: Different executable sizes with same options?

[posguy99]

I'm sure this is me just not actually understanding how clang works. Feel free to label clueless.

Build ksh...

$ bin/package clean && bin/package make
$ ll arch/darwin.i386-64/bin/ksh
-rwxr-xr-x  1 mwilson  staff  1292120 Jul 28 14:26 arch/darwin.i386-64/bin/ksh*

Ok, that’s nice and small.

Build ksh this way...

$ bin/package clean
$ CCFLAGS=-USHOPT_EDPREDICT bin/package make
$ ll arch/darwin.i386-64/bin/ksh
-rwxr-xr-x  1 mwilson  staff  1879776 Jul 28 15:24 arch/darwin.i386-64/bin/ksh*

Huh?

Yes, it's disabled in SHOPT.sh, I never changed the makefile I was building ksh with and the -U has been in it forever. Who cares if I undefine it or not, SHOPT.sh explicitly sets it.

[McDutchie]

The build system currently has an annoying characteristic: if you specify any CCFLAGS, they override the default flags instead of adding to them. I may get around to changing that sometime.

In any case, with clang and gcc, the default CCFLAGS are -Os (optimise for small executable size), so if you add that, you should get an identical executable.

[posguy99]

I don't NEED to specify disabling that any more, since it's disabled by default.

[McDutchie]

Of course. But you wanted to know why your executable was larger. My answer explained that. Because you passed CCFLAGS (any CCFLAGS), the default -Os flag was overridden.

[posguy99]

Yea, I didn't mean to be snarky. Apologies.

[McDutchie]

No worries.