700196 - Unable to create libxul.so due to unresolved symbol _Unwind_GetIP from nsStackwalk.o

Status: RESOLVED INVALID

(Firefox Build System :: General, defect)

Description

[Steve Fink [:sfink] [:s:]]

Attachment: mozconfig

I seem to have somehow gotten my system into a bad state. Whenever I try to build, I get

/usr/bin/ld: error: hidden symbol '_Unwind_GetIP' is not defined locally

while trying to build libxul.so. That's when linking with gold. With ld.bfd, I get

../../xpcom/base/nsStackWalk.o: In function `unwind_callback':
/home/sfink/src/MI-jitprofiler/xpcom/base/nsStackWalk.cpp:1537: undefined reference to `_Unwind_GetIP'

That symbol is from xpcom/base/nsStackwalk.cpp, from #include <libunwind.h> (after -including config/gcc_hidden.h).

% objdump -t nsStackWalk.o | grep GetIP
0000000000000000         *UND*	0000000000000000 .hidden _Unwind_GetIP

It is defined in /lib64/libgcc_s.so.1:

% objdump -T /lib64/libgcc_s.so.1 | grep GetIP 
000000378e40d680 g    DF .text	0000000000000015  GCC_4.2.0   _Unwind_GetIPInfo
000000378e40d670 g    DF .text	0000000000000008  GCC_3.0     _Unwind_GetIP

Adding -lgcc_s to the libxul.so link line doesn't change anything.

This is with an unmodified mozilla-inbound checkout (cf8b201e8980).

Comment 1

[Steve Fink [:sfink] [:s:]]

I found a place where I could do a comparative build, and the difference is that the undefined symbol is not hidden in a proper build.

So it's a compile problem, I guess? (Does it even make sense for undefined symbols to be hidden? What does that mean?)

Comment 2

[Steve Fink [:sfink] [:s:]]

Looks like it's because at some point I installed libunwind into /usr/local, and /usr/local/include is (mysteriously) on my include path.