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Date: Wed, 18 Sep 2013 09:04:17 +0100
From: Andrew Turner <andrew@fubar.geek.nz>
To: Tim Kientzle <kientzle@freebsd.org>
Subject: Re: -ffunction-sections, -fdata-sections and -Wl,--gc-sections
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Cc: Ed Schouten <ed@80386.nl>, FreeBSD Current <freebsd-current@freebsd.org>
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On Sun, 15 Sep 2013 19:30:01 -0700
Tim Kientzle <kientzle@freebsd.org> wrote:

> 
> On Sep 15, 2013, at 2:24 PM, Ed Schouten <ed@80386.nl> wrote:
> > GCC and Clang support the -ffunction-sections and -fdata-sections
> > flags. Essentially, these flags force the compiler to put every
> > function and variable in its own section. Though this will blow up
> > the
> ….
> > - devd suddenly becomes 500 KB in size, instead of a megabyte,
> > - init's size drops from 900 KB to 600 KB,
> 
> Can you figure out what functions are getting omitted
> when you make this change?

You can add "-Wl,--print-gc-sections" to LDFLAGS to print which sections
the linker is removing.

Andrew