re PR c++/27329 (ICE with misplaced expression)
PR c++/27329
PR c++/26938
* cp-tree.h (redeclare_class_template): Adjust declaration
to return bool instead of void.
* pt.c (redeclare_class_template): Update definition. Return
false on error.
* decl.c (xref_tag): Return error_mark_node if redeclare_class_template
returned false.
* g++.dg/template/crash58.C: New test.
* g++.dg/template/crash59.C: New test.
* g++.dg/parse/crash28.C: Adjust error markers.
* g++.dg/template/crash34.C: Likewise.
* g++.dg/template/friend31.C: Likewise.
* g++.dg/template/crash32.C: Likewise.
From-SVN: r117205