[Bug c++/56247] New: internal compiler error: in tsubst_copy, at cp/pt.c:12131

[dsagald8 at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56247

             Bug #: 56247
           Summary: internal compiler error: in tsubst_copy, at
                    cp/pt.c:12131
    Classification: Unclassified
           Product: gcc
           Version: 4.7.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: dsagald8@gmail.com


Created attachment 29392
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=29392
Test case

ICE when the same member function pointer (to a base class's method) is used as
a template parameter from two different methods of the same templated child
class. What's a bit unusual here is that the bug is only triggered if the same
instantiation occurs in two different methods.

The reduced test case is short enough to include directly:

--------
struct Base {
    void method() {}
};  

typedef void (Base::*MemPtr)();

// Template with a member function pointer "non-type parameter".
template<MemPtr func>
struct Wrapper {};

template<class C>
struct Child : public Base {
    // Templated derived class instantiates the Wrapper with the same parameter
    // in two different virtual methods.
    void foo() { typedef Wrapper<&Base::method> W; }
    void bar() { typedef Wrapper<&Base::method> W; }
};

// Instantiate Child with some type. 
template class Child<int>;
--------

Here's the detailed gcc output:
% /usr/local/bin/g++47 -v -save-temps -c bugtest.cc
Using built-in specs.
COLLECT_GCC=/usr/local/bin/g++47
Target: x86_64-portbld-freebsd8.2
Configured with: ./../gcc-4.7-20120818/configure --disable-nls
--enable-languages=c,c++,objc,fortran --libdir=/usr/local/lib/gcc47
--libexecdir=/usr/local/libexec/gcc47 --program-suffix=47
--with-as=/usr/local/bin/as --with-gmp=/usr/local
--with-gxx-include-dir=/usr/local/lib/gcc47/include/c++/
--with-ld=/usr/local/bin/ld --with-libiconv-prefix=/usr/local
--with-pkgversion='FreeBSD Ports Collection' --with-system-zlib
--enable-languages=c,c++,objc,fortran,java --prefix=/usr/local
--mandir=/usr/local/man --infodir=/usr/local/info/gcc47
--build=x86_64-portbld-freebsd8.2
Thread model: posix
gcc version 4.7.2 20120818 (prerelease) (FreeBSD Ports Collection) 
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-c' '-shared-libgcc' '-mtune=generic'
'-march=x86-64'
 /usr/local/libexec/gcc47/gcc/x86_64-portbld-freebsd8.2/4.7.2/cc1plus -E -quiet
-v src/scratch/bugtest.cc -mtune=generic -march=x86-64 -fpch-preprocess -o
bugtest.ii
ignoring nonexistent directory
"/usr/local/lib/gcc47/gcc/x86_64-portbld-freebsd8.2/4.7.2/../../../../../x86_64-portbld-freebsd8.2/include"
#include "..." search starts here:
#include <...> search starts here:
 /usr/local/lib/gcc47/include/c++/
 /usr/local/lib/gcc47/include/c++//x86_64-portbld-freebsd8.2
 /usr/local/lib/gcc47/include/c++//backward
 /usr/local/lib/gcc47/gcc/x86_64-portbld-freebsd8.2/4.7.2/include
 /usr/local/include
 /usr/local/lib/gcc47/gcc/x86_64-portbld-freebsd8.2/4.7.2/include-fixed
 /usr/include
End of search list.
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-c' '-shared-libgcc' '-mtune=generic'
'-march=x86-64'
 /usr/local/libexec/gcc47/gcc/x86_64-portbld-freebsd8.2/4.7.2/cc1plus
-fpreprocessed bugtest.ii -quiet -dumpbase bugtest.cc -mtune=generic
-march=x86-64 -auxbase bugtest -version -o bugtest.s
GNU C++ (FreeBSD Ports Collection) version 4.7.2 20120818 (prerelease)
(x86_64-portbld-freebsd8.2)
        compiled by GNU C version 4.7.2 20120818 (prerelease), GMP version
5.0.1, MPFR version 3.0.0, MPC version 0.8.2
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
GNU C++ (FreeBSD Ports Collection) version 4.7.2 20120818 (prerelease)
(x86_64-portbld-freebsd8.2)
        compiled by GNU C version 4.7.2 20120818 (prerelease), GMP version
5.0.1, MPFR version 3.0.0, MPC version 0.8.2
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
Compiler executable checksum: 4c5936a9f1a6230b2e84e5f997572e48
src/scratch/bugtest.cc: In instantiation of 'void Child<C>::bar() [with C =
int]':
src/scratch/bugtest.cc:21:16:   required from here
src/scratch/bugtest.cc:17:49: internal compiler error: in tsubst_copy, at
cp/pt.c:12131
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.