On Mon, 13 Apr 2009 10:57:37 -0400 ABCD <[email protected]> wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > Jorge Morais wrote: > > I want these two flags (--as-needed and --hash-style=gnu) to be active > > before I adopt GCC 4.3 and recompile world. > > Just as an FYI, you do not need to rebuild the world when you upgrade > GCC - the only time this was needed was around the GCC 3.3 to 3.4 > transition, because of a one-time ABI breakage. > > > By the way, binaries linked with --as-needed are compatible with binaries > > linked without it, yes? > > > > The --as-needed flag simply tells the linker to be more selective about > which libraries to link against -- it does not change anything about the > format, etc. of the library itself (to be precise, using --as-needed > will cause only the NEEDED entries that are actually needed to be > emitted to the final binary). So, to answer your question, yes, they > are perfectly compatible with each other. From http://www.gentoo.org/proj/en/qa/asneeded.xml#doc_chap2
Note: While applying patches to libraries to fix --as-needed support, it is usually not the case to apply a revision bump: those who don't want to use the flag don't need to rebuild the library. For this reason, those who want to use --as-needed are invited to run an emerge -e world so that libraries are rebuilt. This suggests that, to be safe, I should activate --as-needed only *after* the next world compilation. -- Software is like sex: it is better when it is free. --Linus Torvalds
