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From: "austern at apple dot com" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug c++/17736] New: Optimization for global initialization with trivial constructors Date: Wed, 29 Sep 2004 19:35:00 -0000 [thread overview] Message-ID: <20040929193519.17736.austern@apple.com> (raw) Consider the following file: struct X { X() { } }; struct Y { Y() { } }; X x1, x2, x3; Y y1, y2, y3; Compiling this to assembly code with -Os, we can see that the compiler is correctly optimizing away the do-nothing constructors: nothing is being done for any of these six global objects. However, the compiler still generates a do-nothing mod_init function. The relevant part of the assembly file is: .mod_init_func .align 2 .long __GLOBAL__I_x1 ... __GLOBAL__I_x1: LFB9: blr LFE9: At least we're only getting one do-nothing function per translation unit, instead of one per class or one per global. But it would be nice if we didn't get it at all. -- Summary: Optimization for global initialization with trivial constructors Product: gcc Version: 4.0.0 Status: UNCONFIRMED Severity: enhancement Priority: P2 Component: c++ AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: austern at apple dot com CC: gcc-bugs at gcc dot gnu dot org GCC build triplet: powerpc-apple-darwin GCC host triplet: powerpc-apple-darwin GCC target triplet: powerpc-apple-darwin http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17736
next reply other threads:[~2004-09-29 19:35 UTC|newest] Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top 2004-09-29 19:35 austern at apple dot com [this message] 2004-09-29 20:14 ` [Bug c++/17736] " bangerth at dealii dot org 2004-09-29 22:26 ` [Bug middle-end/17736] " pinskia at gcc dot gnu dot org
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