On 23/05/16 14:24, MM wrote: > On 23 May 2016 at 12:53, Szabolcs Nagy <szabolcs.n...@arm.com> wrote: >> On 23/05/16 12:36, MM wrote: >>> Hello, >>> >>> g++ (GCC) 5.3.1 20160406 (Red Hat 5.3.1-6) >>> GNU gold (version 2.25-17.fc23) 1.11 >>> I successfully link a executable in debug mode (-std=c++11 -g) but not in >>> release mode (-std=c++11 -flto -O3). All sources are compiled with the same >>> option. Shared libraries are used. >>> The compiler driver is used to launch the final link line: >>> /bin/c++ -std=c++11 -Wno-multichar -O3 -DNDEBUG -flto <listofOfiles> >>> -o <executable> -rdynamic <listofsolibs> Wl,-rpath,<longlistofdirs> >>> >>> These are the errors I see (only in release, not in debug): >>> ... [clone .constprop.79]: error: undefined reference to >>> 'typeinfo for <ns1>::<ns2>::market [clone .lto_priv.1353]' >>> >>> Both the debug and release version of the object referencing this show the >>> same with gcc-nm: >>> >>> U typeinfo for <ns1>::<ns2>::market >>> Note this bit " [clone .lto_priv.1353]" is not in the symbol at all. >>> >>> This is what gcc-nm says for the object where the symbol is defined >>> (market.cpp.o, which is part of libmarkets.so): >>> >>> 1. In DEBUG >>> gcc-nm -C market.cpp.o | grep 'typeinfo for <ns1>::<ns2>::market' >>> 0000000000000000 V typeinfo for <ns1>::<ns2>::market >>> >>> 2. In RELEASE >>> gcc-nm -C market.cpp.o | grep 'typeinfo for <ns1>::<ns2>::market' >>> 00000000 W typeinfo for <ns1>::<ns2>::market >>> This is the one that fails. >>> Given the versions of gcc and ld, the default behaviour for lto should be >>> straightforward? >>> Any ideas what's going on? >>> >> >> typeinfo seems to be a weak object symbol >> which is known to be broken with lto, so >> this may be related to: >> >> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69271 >> > > Is it a workaround to not compile the referencing cpp and the referred > cpp without lto, yet compile all the rest and link with lto? > Otherwise, I'll turn off LTO until that bug is resolved.
it is not clear if this the same issue as pr692771, so i think you should submit a bug report with test code if possible. > > Thanks >
