I have passed to compile a little temporary useless C++ code and G++ have written me "Please submit a full bug report", so I do it.

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error description
*************************************************************************
6.cpp:15: internal compiler error: in is_ancestor, at cp/name-lookup.c:2222
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://gcc.gnu.org/bugs.html> for instructions.

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cmdline:
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gpp -S -W -Wextra -g -O2 -v -save-temps 6.cpp >output

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output:
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Using built-in specs.
Target: djgpp
Configured with: /gnu/gcc-4.10/configure djgpp --prefix=/dev/env/DJDIR --disable-nls --disable-werror --enable-languages=c,c++,fortran,objc,obj-c++,ada
Thread model: single
gcc version 4.1.0
 p:/djgpp/bin/../libexec/gcc/djgpp/4.10/cc1plus.exe -E -quiet -v -iprefix p:/djgpp/bin/../lib/gcc/djgpp/4.10/ -remap -imacros p:/djgpp/bin/../lib/gcc/djgpp/4.10/djgpp.ver 6.cpp -mtune=pentium -W -Wextra -fworking-directory -O2 -fpch-preprocess -o 6.ii
ignoring nonexistent directory "p:/djgpp/bin/../lib/gcc/djgpp/4.10/../../../../djgpp/include"
ignoring nonexistent directory "p:/djgpp/djgpp/include/"
#include "..." search starts here:
#include <...> search starts here:
 p:/djgpp/bin/../lib/gcc/djgpp/4.10/../../../../include/cxx/4.10
 p:/djgpp/bin/../lib/gcc/djgpp/4.10/../../../../include/cxx/4.10/djgpp
 p:/djgpp/bin/../lib/gcc/djgpp/4.10/../../../../include/cxx/4.10/backward
 p:/djgpp/bin/../lib/gcc/djgpp/4.10/include
 p:/djgpp/include/cxx/4.10/
 p:/djgpp/include/cxx/4.10/djgpp/
 p:/djgpp/include/cxx/4.10/backward/
 p:/djgpp/lib/gcc/djgpp/4.10/include/
 p:/djgpp/include/
End of search list.
 p:/djgpp/bin/../libexec/gcc/djgpp/4.10/cc1plus.exe -fpreprocessed 6.ii -quiet -dumpbase 6.cpp -mtune=pentium -auxbase 6 -g -O2 -W -Wextra -version -o 6.s
GNU C++ version 4.1.0 (djgpp)
	compiled by GNU C version 4.1.0.
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
Compiler executable checksum: 25d99bb4bc1ed4eaee3f5ab2997c0cc8
6.cpp:15: internal compiler error: in is_ancestor, at cp/name-lookup.c:2222
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://gcc.gnu.org/bugs.html> for instructions.

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6.cpp:
*************************************************************************
#define heap

template<class T>
struct User_wrapper
{ 
    User_wrapper(T heap *const);
};

struct X
{
    static User_wrapper<X>    test(X heap* ptr);
};

template<class T>
User_wrapper<T> 	T::test(T heap* ptr)
{
    return User_wrapper<T>(ptr);
}

int		main()
{

}

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6.ii:
*************************************************************************
# 1 "6.cpp"
# 1 "p:/prj/educh/os/lib/#data/test/v4//"
# 1 "<built-in>"
# 1 "<command line>"
# 1 "p:/djgpp/bin/../lib/gcc/djgpp/4.10/djgpp.ver" 1
# 1 "p:/djgpp/include/sys/version.h" 1 3 4
# 2 "p:/djgpp/bin/../lib/gcc/djgpp/4.10/djgpp.ver" 2
# 1 "<command line>" 2
# 1 "6.cpp"


template<class T>
struct User_wrapper
{
 User_wrapper(T *const);
};

struct X
{
 static User_wrapper<X> test(X * ptr);
};

template<class T>
User_wrapper<T> T::test(T * ptr)
{
 return User_wrapper<T>(ptr);
}

int main()
{

}

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6.S:
*************************************************************************
	.file	"6.cpp"
	.section	.debug_abbrev,""
Ldebug_abbrev0:
	.section	.debug_info,""
Ldebug_info0:
	.section	.debug_line,""
Ldebug_line0:
	.section .text
Ltext0: