Bug 134162 – [4.1/bad-code?] #pragma GCC visibility causes non-PIC code generation

• Status: RESOLVED FIXED
• Product: Gentoo Linux

[Description Diego Elio Pettenò (RETIRED) 2006-05-23 18:23:25 UTC]

I know that visibility support is still unsafe, although upstream GCC and KDE continue saying that it's all well... I know GCC 4.1 seems to fix the -fvisibility-inlines-hidden problem with -fPIC.. but seems like #pragma still have issues.

I'm going to attach a (bzip2 compressed) copy of the preprocessed output generated by rubytag++, that, once compiled, fails badly:

flame@enterprise ~/tmp $ gcc -shared -fPIC rubytagpp.ii -o rubytagpp-test.so
/usr/lib/gcc/x86_64-pc-linux-gnu/4.1.1-pre20060517/../../../../x86_64-pc-linux-gnu/bin/ld: warning: creating a DT_TEXTREL in object.
/usr/lib/gcc/x86_64-pc-linux-gnu/4.1.1-pre20060517/../../../../x86_64-pc-linux-gnu/bin/ld: /tmp/ccZUhVew.o: relocation R_X86_64_PC32 against `rb_define_module' can not be used when making a shared object; recompile with -fPIC
/usr/lib/gcc/x86_64-pc-linux-gnu/4.1.1-pre20060517/../../../../x86_64-pc-linux-gnu/bin/ld: final link failed: Bad value
collect2: ld returned 1 exit status

Hope this can help to find what it's still wrong with it.

Diego

[Comment 1 Diego Elio Pettenò (RETIRED) 2006-05-23 18:24:52 UTC]

Created attachment 87353 [details]
rubytagpp.ii.bz2

[Comment 2 Mark Loeser (RETIRED) 2006-05-26 22:44:31 UTC]

Here's a reduced testcase.  I'll try to do some debugging and talk to upstream to make sure this isn't intended behaviour...I'm sure it isn't :)

#pragma GCC visibility push(hidden)
void rb_check_type (int, int);
class AudioProperties
{};

AudioProperties * ruby2TagLib_AudioPropertiesPtr (int rval)
{
    do
    {
        rb_check_type (rval, 0x22);
    } while (0);
}

[Comment 3 Mark Loeser (RETIRED) 2006-05-26 23:27:28 UTC]

Actually, I think that testcase just shows another way to get a textrel...I'll have to look into this more.

[Comment 4 Jakub Moc (RETIRED) 2007-03-10 17:54:29 UTC]

*** Bug 170289 has been marked as a duplicate of this bug. ***

[Comment 5 SpanKY 2007-03-10 22:20:54 UTC]

looks like it'll prob stay broken until gcc-4.2.0 is released ... the required changes are just too invasive for any one here to watch over

[Comment 6 Mark Loeser (RETIRED) 2007-12-09 03:07:03 UTC]

Do we want to keep this open until gcc-4.2 is stable?  (Its in the tree atleast, and I'm pretty sure Diego was running ~arch to hit this bug when he did)

[Comment 7 Diego Elio Pettenò (RETIRED) 2008-12-23 20:01:10 UTC]

I'd close this since anyway 4.1 is broken a lot regarding visibility, so it's not much of a problem.

[Comment 8 Mark Loeser (RETIRED) 2009-05-01 01:16:16 UTC]

Fixed in newer versions of gcc.