c++/3015: Internal compiler error on illegal code

[RDBrown@mira.net]

Using the testcase supplied with the PR, the problem remains in 2.95.2
but is fixed in 3.0 20010527 (prerelease).

+ /usr/bin/gcc -c -v pr3015.ii
Reading specs from /usr/lib/gcc-lib/i386-linux/2.95.2/specs
gcc version 2.95.2 20000220 (Debian GNU/Linux)
 /usr/lib/gcc-lib/i386-linux/2.95.2/cc1plus pr3015.ii -quiet -version -o /tmp/cc1iVCqf.s
GNU C++ version 2.95.2 20000220 (Debian GNU/Linux) (i386-linux) compiled by GNU C version 2.95.2 20000220 (Debian GNU/Linux).
pr3015.ii:7: Internal compiler error 19970302.
pr3015.ii:7: Please submit a full bug report.
pr3015.ii:7: See <URL: http://www.gnu.org/software/gcc/bugs.html > for instructions.
+ gcc -c -v pr3015.ii
Reading specs from /usr/local/bin/../lib/gcc-lib/i386-pc-linux-gnu/3.0/specs
Configured with: ../configure --prefix=/tmp/gcc-20010527-root/usr/local --enable-shared --enable-threads --disable-checking i386-pc-linux-gnu
Thread model: posix
gcc version 3.0 20010527 (prerelease)
 /usr/local/bin/../lib/gcc-lib/i386-pc-linux-gnu/3.0/cc1plus -fpreprocessed pr3015.ii -quiet -dumpbase pr3015.ii -version -o /tmp/ccvtcj9n.s
GNU CPP version 3.0 20010527 (prerelease) (cpplib) (i386 Linux/ELF)
GNU C++ version 3.0 20010527 (prerelease) (i386-pc-linux-gnu)
	compiled by GNU C version 3.0 20010527 (prerelease).
pr3015.ii:6: size of member `mt' is not constant