inline-asm/10386: Passing fct ptr to inline asm not PIC-safe

[drepper at redhat dot com]

>Number:         10386
>Category:       inline-asm
>Synopsis:       Passing fct ptr to inline asm not PIC-safe
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Apr 12 08:26:01 UTC 2003
>Closed-Date:
>Last-Modified:
>Originator:     Ulrich Drepper
>Release:        gcc version 3.3 20030412 (prerelease)
>Organization:
>Environment:
Linux/x86-64
>Description:
Using a function pointer as a asm parameter in PIC code fails if the asm parameter format includes "i".  In this case the compiler generates an immediate parameter which it should, since the actual format is "ir", use a register and compute the value in a position independent way.
>How-To-Repeat:
Compile the attached file with

  gcc33 -shared -fPIC -o u.so -O2 -g u.c

The result is

/usr/bin/ld: /tmp/ccYnmTnc.o: relocation R_X86_64_32S can not be used when making a shared object; recompile with -fPIC
/tmp/ccYnmTnc.o: could not read symbols: Bad value


since the generated code is

        movq $foo, %rax
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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