https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61577
--- Comment #198 from Peter Bisroev <peter.bisroev at groundlabs dot com> --- (In reply to dave.anglin from comment #196) > If you create a second object file with a second instance of hello, the > linker should not > complain about the second definition of hello since it is weak. It would > complain about > two global instances. Hi Dave, I have created a new object hello2.o, and when I tried to link I got ------------------------------ "ld: Duplicate symbol "hello" in files hello.o and hello2.o " ------------------------------ Then I realized that in hello.s hello is defined as ".global hello". Changing that to '.weak hello', reassembling and relinking all worked. I guess this confirms what I have seen in comment 187. So this seems to work as expected. This worked both with aCC and gcc. > Could you test whether the "brl" branch works? Simply take your main.s file > and edit the branch > to hello. This should show whether the assembler can handle it. If it > assembles, look at relocation > and see if program will link. I took main.s generated by aCC. Made the following changes: ------------------------------ $ diff main-aCC.s main-aCC-weak-brl.s 7c7 < .global hello --- > .weak hello 41c41 < br.call.dptk.many rp = hello# ;; // B [main.cc: 10/5] --- > brl.call.dptk.many rp = hello# ;; // B [main.cc: 10/5] ------------------------------ Reassembled with HP's as, relinked and the test ran fine. With this change when hello was global PCREL21B relocation was used. When I changed hello to weak, PCREL21B was still used. When I changed this to weak with a brl, PCREL60B was used. I have then tried to do a similar thing with main.s generated by gcc. ------------------------------ $ diff main-gcc.s main-gcc-brl.s 19c19 < br.call.sptk.many b0 = hello# --- > brl.call.sptk.many b0 = hello# ------------------------------ Reassembled with GNU's as and relinked. PCREL21B changes to PCREL60B, but when I try to run the binary I get an "Illegal instruction" and a core dump. The illegal instruction seems to be the brl. I know almost nothing of IA-64 assembly, so will read up a bit more and try to figure out what is going on there. Please let me know if I have missed anything. Thanks! --peter
