------- Comment #3 from matz at gcc dot gnu dot org 2010-01-15 15:06 -------
input_location handling is broken.
(gdb) bt
#0 0x00007ffff704a7c3 in strcmp () from /lib64/libc.so.6
#1 0x00000000011be858 in splay_tree_splay (sp=0x1824110, key=0)
at ../../gcc/libiberty/splay-tree.c:148
#2 0x00000000011beed6 in splay_tree_lookup (sp=0x1824110, key=0)
at ../../gcc/libiberty/splay-tree.c:389
#3 0x00000000007b162a in get_fileinfo (name=0x0) at ../../gcc/gcc/c-lex.c:114
note: name==0, this comes from:
#25 0x0000000000765939 in fname_as_string (pretty_p=1)
at ../../gcc/gcc/c-common.c:950
#26 0x00000000004e0b3a in cp_make_fname_decl (loc=1708071, id=0x7ffff7e91ec8,
type_dep=1) at ../../gcc/gcc/cp/decl.c:3559
#27 0x0000000000765a7a in fname_decl (loc=1708071, rid=67, id=0x7ffff7e91ec8)
at ../../gcc/gcc/c-common.c:999
Where the block in c-common.c is:
995 location_t saved_location = input_location;
996 input_location = UNKNOWN_LOCATION;
997
998 stmts = push_stmt_list ();
999 decl = (*make_fname_decl) (loc, id, fname_vars[ix].pretty);
I.e. input_location is reset (that is okay here), then through the
make_fname_decl call the c++ frontend is called back, which tries to construct
a decl, implicitely (via cxx_make_type) accessing the fileinfo for
input_filename.
We want to create the __PRETTY_FUNCTION__ string decl here.
I can't say if it's more sensible if the C++ frontend would deal with
input_location==UNKNOWN_LOCATION sometimes, or if c-common.c should be changed
to not reset it temporarily. But the latter really makes sense here, as the
__PRETTY_FUNCTION__ decl is created on demand, i.e. a random place, which it
then would get.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42758
