File a.d:
import b: c;


File b.d:
import std.typetuple : TypeTuple;
alias c = TypeTuple!(' ');


Command: "gdc a.d"

compiler information:
gdc (GCC) 4.10.0 20140506 (experimental)
Compiled from git master rev 83b13e669914f114a9708c966fcde857ff1b274b

Output:
Dsymbol::toSymbol() 'TList', kind = 'tuple'
a.d:1: internal compiler error: in toSymbol, at d/d-decls.cc:71
0x65a2b7 Dsymbol::toSymbol()
    ../../../gcctrunk/gcc/d/d-decls.cc:71
0x65a4f2 Dsymbol::toImport()
    ../../../gcctrunk/gcc/d/d-decls.cc:111
0x66ab71 Dsymbol::toObjFile(int)
    ../../../gcctrunk/gcc/d/d-objfile.cc:105
0x67013e Module::genobjfile(int)
    ../../../gcctrunk/gcc/d/d-objfile.cc:1477
0x659d02 d_parse_file()
    ../../../gcctrunk/gcc/d/d-lang.cc:1132
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions.