[Bug other/29971] New: anonymous namespace vs deprecated static keyword (different linkage).

["pluto at agmk dot net" <gcc-bugzilla at gcc dot gnu dot org>]

in theory the anonymous namespace is a `static' keyword superior.
in fact it breaks applications that use dlopen() with RTLD_GLOBAL.
the so called superior emits symbols with different binding.

e.g.:

static keyword:
 00000000 4 OBJECT  LOCAL  DEFAULT  4 N::a_

namespace superior:
 00000000 4 OBJECT  GLOBAL DEFAULT  4 N::(anonymous namespace)::a_


$ make CPPFLAGS=-DSUPERIOR && ./main
i486-gnu-linux-g++ -Wall -O1 -g0 -s -DSUPERIOR *.cpp -c
i486-gnu-linux-g++ -Wall -O1 -g0 -s -DSUPERIOR m1.o A.o -o libm1.so -shared
i486-gnu-linux-g++ -Wall -O1 -g0 -s -DSUPERIOR m2.o A.o -o libm2.so -shared
i486-gnu-linux-g++ -Wall -O1 -g0 -s -DSUPERIOR main.cpp -o main -ldl
i486-gnu-linux-strip --strip-unneeded *.so main
i1 = 0x55b6b4
i2 = 0x55b6b4
Aborted

$ make && ./main
i486-gnu-linux-g++ -Wall -O1 -g0 -s  *.cpp -c
i486-gnu-linux-g++ -Wall -O1 -g0 -s  m1.o A.o -o libm1.so -shared
i486-gnu-linux-g++ -Wall -O1 -g0 -s  m2.o A.o -o libm2.so -shared
i486-gnu-linux-g++ -Wall -O1 -g0 -s  main.cpp -o main -ldl
i486-gnu-linux-strip --strip-unneeded *.so main
i1 = 0x759670
i2 = 0x112670


-- 
           Summary: anonymous namespace vs deprecated static keyword
                    (different linkage).
           Product: gcc
           Version: 4.1.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: other
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: pluto at agmk dot net
GCC target triplet: elf-*


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29971