Bug 733162

Summary: icu-4.4.1-3.fc14 fails to build on ARM due to gcc bug
Product: [Fedora] Fedora Reporter: Daniel Drake <dsd>
Component: icuAssignee: Caolan McNamara <caolanm>
Status: CLOSED NEXTRELEASE QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 14CC: caolanm, denis.arnaud_fedora, jakub, pbrobinson
Target Milestone: ---   
Target Release: ---   
Hardware: arm7   
OS: Unspecified   
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2011-08-25 07:33:30 EDT Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: ---
Bug Depends On:    
Bug Blocks: 245418    
Description Flags
test case with instructions inside
icu workaround to avoid using GCC atomic builtins on ARM none

Description Daniel Drake 2011-08-24 19:02:30 EDT
Created attachment 519738 [details]
test case with instructions inside

icu fails to build for ARM on f14:

/usr/bin/ld: ../../make[2]: Leaving directory `/builddir/build/BUILD/icu/source/tools/makeconv'
bin/makeconv: hidden symbol `__sync_val_compare_and_swap_4' in /usr/lib/gcc/armv5tel-redhat-linux-gnueabi/4.5.1/libgcc.a(linux-atomic.o) is referenced by DSO
/usr/bin/ld: final link failed: Nonrepresentable section on output
collect2: ld returned 1 exit status

This is somehow related to http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40134
however, the patches mentioned there are shipped in F14 gcc. hmm.

I narrowed this down to a small test case, which I will attach. To summarise, when using GCC's inbuilt atomic functions in a DSO linked with g++, the atomic function code doesn't get copied from libgcc.a into the output DSO like it should. If linking with gcc instead of g++, it works fine.

The test case is already confirmed to work on F15, so even though this is a gcc bug, I think it would be acceptable to work around this in F14 within the icu package, and dedicate our time to moving to F15+ ASAP.

I'm attaching my proposed workaround. Also, an already-upstream patch is needed from http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=589076

then it builds OK :)
Comment 1 Daniel Drake 2011-08-24 19:10:33 EDT
Created attachment 519741 [details]
icu workaround to avoid using GCC atomic builtins on ARM
Comment 2 Caolan McNamara 2011-08-25 04:54:31 EDT
Checked in both fixes to F14, and the asm one for F15. F16 onwards should have the asm fix already.

That sufficient, or anything else needed ?
Comment 3 Peter Robinson 2011-08-25 11:13:12 EDT
> That sufficient, or anything else needed ?

Absolutely perfect! Thanks for the fixes to all branches and the very quick response :)