Re: removing unused functions during final link

[Melvin Blades <melvin.blades@gmail.com>]

For a simple example I created 3 files.
     root.c  -- has main() which calls one function in show.c
     show.c - has two functions, one is called by main, one is not
called. ( both use puts to print a message.)
     show2.c -- has two functions. Neither are called

--------Makefile--------

OBJS := root.o show.o show2.o
SOURCE := root.c show.c show2.c

all: $(SOURCE)
        ${CC} -mips32 -fdata-sections -ffunction-sections -c $(SOURCE)
        ${CC} $(OBJS)  -Wl,--gc-sections -o root.exe
-------End --------

The resulting executable contains the texts strings and function names
from both functions in show.c and neither function of show2.c  My
usage of -fdata-section -ffunction-section and -gc-sections prevents
the  functions in show2.c from being linked in , but not the unused
functions in show.c

$home/dev1/>file root.exe
root.exe: ELF 32-bit LSB executable, MIPS, MIPS32 version 1 (SYSV),
dynamically linked (uses shared libs), not stripped

~

On Wed, Sep 3, 2014 at 3:21 AM, Andrew Haley <aph@redhat.com> wrote:
> On 09/03/2014 04:20 AM, Melvin Blades wrote:
>> Using gcc instead of ld, I was able to get it to strip unused
>>  functions if all the functions in a file are not called.
>>  But I could not get it to strip  unused functions if they  are in the
>>  same source file as used functions .
>>
>>  Is there a way to get it strip ALL the unused functions?
>
> That should have worked.  Please tell us the exact command you used.
>
> Andrew.
>
>