[ILUG] shared libraries

[Aidan Kehoe]

 Ar an 15u la de mi 10, scriobh John P. Looney :

 >  -fpic, or not to -fpic ?
 > 
 >  I just noticed that I had a Makefile of shared lib I was using without
 > any mention of "-fpic". Does GCC generate it by default now or something ?
 > Because it was working fine, and "gcc -shared" didn't moan at me...
 > 

Depends on the architecture, I think. Ah, here we are ... OpenBSD
sparc, 

12:37PM ~ > make c.o
cc -Wall -W -Wshadow -Wformat -pedantic -O3 -g  -c c.c
c.c: In function `our_main':
c.c:12: warning: flag `#' used with type `p'
12:37PM ~ > cc -shared -o c.so c.o
ld: c.o: RRS text relocation at 0x30 for "_malloc"
ld: c.o: RRS text relocation at 0x40 for "_printf"
12:38PM ~ >  # (fails) . 
12:38PM ~ > cc -Wall -W -Wshadow -Wformat -pedantic -O3 -g -fPIC -c c.c 
c.c: In function `our_main':
c.c:12: warning: flag `#' used with type `p'
12:38PM ~ > cc -shared -o c.so c.o                                      
12:38PM ~ > file c.so
c.so: OpenBSD/sparc demand paged shared library not stripped
12:38PM ~ > 

vs. Red Hat Linux release 6.1 ; 

7:40am ~ > cc -Wall -W -Wshadow -Wformat -pedantic -O3 -g  -c c.c
c.c: In function `our_main':
c.c:12: warning: flag `#' used with type `p'
7:40am ~ > cc -shared -o c.so c.o
7:40am ~ > file c.so
c.so: ELF 32-bit LSB shared object, Intel 80386, version 1, not stripped
7:40am ~ > 

Has someone got Linux on another architecture kicking around to
verify that?

-- 
`... when the elephant man broke strong men's necks, when he'd had too 
many Powers, ...'