Declaring the explicit specialization of the member of the class template causes the compiler to 'forget' to emit the out-of-line symbol for the explicit specialization defined later. $ cat t.cpp template <class T> struct S { int foo () { return 0; } }; template <> int S<int>::foo (); template <> int S<int>::foo () { return 1; } $ g++ -c -v t.cpp Reading specs from /usr/local/gcc-3.0/lib/gcc-lib/i686-pc-linux-gnu/3.0/specs Configured with: ../gcc-3.0/configure --prefix=/usr/local/gcc-3.0 --enable-shared Thread model: single gcc version 3.0 /usr/local/gcc-3.0/lib/gcc-lib/i686-pc-linux-gnu/3.0/cc1plus -v -D__GNUC__=3 -D__GNUC_MINOR__=0 -D__GNUC_PATCHLEVEL__=0 -D__ELF__ -Dunix -Dlinux -D__ELF__ -D__unix__ -D__linux__ -D__unix -D__linux -Asystem=posix -D__NO_INLINE__ -D__STDC_HOSTED__=1 -D_GNU_SOURCE -Acpu=i386 -Amachine=i386 -Di386 -D__i386 -D__i386__ -D__tune_i686__ -D__tune_pentiumpro__ t.cpp -D__GNUG__=3 -D__GXX_DEPRECATED -D__EXCEPTIONS -D__GXX_ABI_VERSION=100 -quiet -dumpbase t.cpp -version -o /tmp/ccoYegSb.s GNU CPP version 3.0 (cpplib) (i386 Linux/ELF) GNU C++ version 3.0 (i686-pc-linux-gnu) compiled by GNU C version 2.95.2 19991024 (release). ignoring nonexistent directory "/usr/local/gcc-3.0/i686-pc-linux-gnu/include" #include "..." search starts here: #include <...> search starts here: /usr/local/gcc-3.0/include/g++-v3 /usr/local/gcc-3.0/include/g++-v3/i686-pc-linux-gnu /usr/local/gcc-3.0/include/g++-v3/backward /usr/local/gcc-3.0/include /usr/local/gcc-3.0/lib/gcc-lib/i686-pc-linux-gnu/3.0/include /usr/include End of search list. as --traditional-format -V -Qy -o t.o /tmp/ccoYegSb.s GNU assembler version 2.9.1 (i386-redhat-linux), using BFD version 2.9.1.0.23 $ nm t.o $ Release: gcc version 3.0 How-To-Repeat: template <class T> struct S { int foo () { return 0; } }; template <> int S<int>::foo (); template <> int S<int>::foo () { return 1; }
Fix: Omit the declaration of the specialization or the definition of the member of the primary template (neither is acceptable if the specialization is to exist in a portable library).
State-Changed-From-To: open->analyzed State-Changed-Why: Confirmed.
Responsible-Changed-From-To: unassigned->lerdsuwa Responsible-Changed-Why: Patch in progress.
State-Changed-From-To: analyzed->closed State-Changed-Why: Fixed in the main trunk (future GCC 3.3).
From: lerdsuwa@gcc.gnu.org To: gcc-gnats@gcc.gnu.org Cc: Subject: c++/3797 Date: 17 Jul 2002 14:07:43 -0000 CVSROOT: /cvs/gcc Module name: gcc Changes by: lerdsuwa@gcc.gnu.org 2002-07-17 07:07:43 Modified files: gcc/cp : ChangeLog decl.c Log message: PR c++/3797 * decl.c (duplicate_decls): Don't propagate inlining parameters from olddecl to newdecl when newdecl is a specialization of the instantiation olddecl. Patches: http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/ChangeLog.diff?cvsroot=gcc&r1=1.2884&r2=1.2885 http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/decl.c.diff?cvsroot=gcc&r1=1.920&r2=1.921