The fix for bug 59195: [C++ demangler handles conversion operator incorrectly] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59195 unfortunately makes the demangler crash due to infinite recursion, in case of casts in template parameters. For example, with: template<int> struct A {}; template <typename Y> void function_temp(A<sizeof ((Y)(999))>) {} template void function_temp<int>(A<sizeof (int)>); The 'function_temp<int>' instantiation above mangles to: _Z13function_tempIiEv1AIXszcvT_Li999EEE The demangler parses this as: typed name template name 'function_temp' template argument list builtin type int function type builtin type void argument list template (*) name 'A' template argument list unary operator operator sizeof unary operator cast template parameter 0 (**) literal builtin type int name '999' And after the fix for 59195, due to: static void d_print_cast (struct d_print_info *dpi, int options, const struct demangle_component *dc) { ... /* For a cast operator, we need the template parameters from the enclosing template in scope for processing the type. */ if (dpi->current_template != NULL) { dpt.next = dpi->templates; dpi->templates = &dpt; dpt.template_decl = dpi->current_template; } when printing the template argument list of A (what should be "<sizeof (int)>"), the template parameter 0 (that is, "T_", the '**' above) now refers to the first parameter of the the template argument list of the 'A' template (the '*' above), exactly what we were already trying to print. This leads to infinite recursion, and stack exaustion. The template parameter 0 should actually refer to the first parameter of the 'function_temp' template. Where it reads "for the cast operator" in the comment in d_print_cast (above), it's really talking about a conversion operator, like: struct A { template <typename U> explicit operator U(); }; We don't want to inject the template parameters from the enclosing template in scope when processing a cast _expression_, only when handling a conversion operator. The problem is that DEMANGLE_COMPONENT_CAST is currently ambiguous, and means _both_ 'conversion operator' and 'cast expression'. Fix this by adding a new DEMANGLE_COMPONENT_CONVERSION component type, which does what DEMANGLE_COMPONENT_CAST does today, and making DEMANGLE_COMPONENT_CAST just simply print its component subtree. I think we could instead reuse DEMANGLE_COMPONENT_CAST and in d_print_comp_inner still do: @@ -5001,9 +5013,9 @@ d_print_comp_inner (struct d_print_info *dpi, int options, d_print_comp (dpi, options, dc->u.s_extended_operator.name); return; case DEMANGLE_COMPONENT_CAST: d_append_string (dpi, "operator "); - d_print_cast (dpi, options, dc); + d_print_conversion (dpi, options, dc); return; leaving the unary cast case below calling d_print_cast, but seems to me that spliting the component types makes it easier to reason about the code. g++'s testsuite actually generates three symbols that crash the demangler in the same way. I've added those as tests in the demangler testsuite as well. And then this fixes PR other/61233 too, which happens to be a demangler crash originally reported to GDB, at: https://sourceware.org/bugzilla/show_bug.cgi?id=16957 Bootstrapped and regtested on x86_64 Fedora 20. Also ran this through GDB's testsuite. GDB will require a small update to use DEMANGLE_COMPONENT_CONVERSION in one place it's using DEMANGLE_COMPONENT_CAST in its sources. libiberty/ 2015-11-27 Pedro Alves <palves@redhat.com> PR other/61321 PR other/61233 * demangle.h (enum demangle_component_type) <DEMANGLE_COMPONENT_CONVERSION>: New value. * cp-demangle.c (d_demangle_callback, d_make_comp): Handle DEMANGLE_COMPONENT_CONVERSION. (is_ctor_dtor_or_conversion): Handle DEMANGLE_COMPONENT_CONVERSION instead of DEMANGLE_COMPONENT_CAST. (d_operator_name): Return a DEMANGLE_COMPONENT_CONVERSION component if handling a conversion. (d_count_templates_scopes, d_print_comp_inner): Handle DEMANGLE_COMPONENT_CONVERSION. (d_print_comp_inner): Handle DEMANGLE_COMPONENT_CONVERSION instead of DEMANGLE_COMPONENT_CAST. (d_print_cast): Rename as ... (d_print_conversion): ... this. Adjust comments. (d_print_cast): Rewrite - simply print the left subcomponent. * cp-demint.c (cplus_demangle_fill_component): Handle DEMANGLE_COMPONENT_CONVERSION. * testsuite/demangle-expected: Add tests. From-SVN: r231020 |
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config | ||
testsuite | ||
.gitignore | ||
COPYING.LIB | ||
ChangeLog | ||
ChangeLog.jit | ||
Makefile.in | ||
README | ||
_doprnt.c | ||
aclocal.m4 | ||
alloca.c | ||
argv.c | ||
asprintf.c | ||
at-file.texi | ||
atexit.c | ||
basename.c | ||
bcmp.c | ||
bcopy.c | ||
bsearch.c | ||
bzero.c | ||
calloc.c | ||
choose-temp.c | ||
clock.c | ||
concat.c | ||
config.h-vms | ||
config.in | ||
configure | ||
configure.ac | ||
configure.com | ||
copying-lib.texi | ||
copysign.c | ||
cp-demangle.c | ||
cp-demangle.h | ||
cp-demint.c | ||
cplus-dem.c | ||
crc32.c | ||
d-demangle.c | ||
dwarfnames.c | ||
dyn-string.c | ||
fdmatch.c | ||
ffs.c | ||
fibheap.c | ||
filename_cmp.c | ||
floatformat.c | ||
fnmatch.c | ||
fnmatch.txh | ||
fopen_unlocked.c | ||
functions.texi | ||
gather-docs | ||
getcwd.c | ||
getopt.c | ||
getopt1.c | ||
getpagesize.c | ||
getpwd.c | ||
getruntime.c | ||
gettimeofday.c | ||
hashtab.c | ||
hex.c | ||
index.c | ||
insque.c | ||
lbasename.c | ||
libiberty.texi | ||
lrealpath.c | ||
maint-tool | ||
make-relative-prefix.c | ||
make-temp-file.c | ||
makefile.vms | ||
md5.c | ||
memchr.c | ||
memcmp.c | ||
memcpy.c | ||
memmem.c | ||
memmove.c | ||
mempcpy.c | ||
memset.c | ||
mkstemps.c | ||
msdos.c | ||
objalloc.c | ||
obstack.c | ||
obstacks.texi | ||
partition.c | ||
pex-common.c | ||
pex-common.h | ||
pex-djgpp.c | ||
pex-msdos.c | ||
pex-one.c | ||
pex-unix.c | ||
pex-win32.c | ||
pexecute.c | ||
pexecute.txh | ||
physmem.c | ||
putenv.c | ||
random.c | ||
regex.c | ||
rename.c | ||
rindex.c | ||
safe-ctype.c | ||
setenv.c | ||
setproctitle.c | ||
sha1.c | ||
sigsetmask.c | ||
simple-object-coff.c | ||
simple-object-common.h | ||
simple-object-elf.c | ||
simple-object-mach-o.c | ||
simple-object-xcoff.c | ||
simple-object.c | ||
simple-object.txh | ||
snprintf.c | ||
sort.c | ||
spaces.c | ||
splay-tree.c | ||
stack-limit.c | ||
stpcpy.c | ||
stpncpy.c | ||
strcasecmp.c | ||
strchr.c | ||
strdup.c | ||
strerror.c | ||
strncasecmp.c | ||
strncmp.c | ||
strndup.c | ||
strnlen.c | ||
strrchr.c | ||
strsignal.c | ||
strstr.c | ||
strtod.c | ||
strtol.c | ||
strtoll.c | ||
strtoul.c | ||
strtoull.c | ||
strverscmp.c | ||
timeval-utils.c | ||
tmpnam.c | ||
unlink-if-ordinary.c | ||
vasprintf.c | ||
vfork.c | ||
vfprintf.c | ||
vprintf-support.c | ||
vprintf-support.h | ||
vprintf.c | ||
vsnprintf.c | ||
vsprintf.c | ||
waitpid.c | ||
xasprintf.c | ||
xatexit.c | ||
xexit.c | ||
xmalloc.c | ||
xmemdup.c | ||
xstrdup.c | ||
xstrerror.c | ||
xstrndup.c | ||
xvasprintf.c |
README
This directory contains the -liberty library of free software. It is a collection of subroutines used by various GNU programs. Current members include: getopt -- get options from command line obstack -- stacks of arbitrarily-sized objects strerror -- error message strings corresponding to errno strtol -- string-to-long conversion strtoul -- string-to-unsigned-long conversion We expect many of the GNU subroutines that are floating around to eventually arrive here. The library must be configured from the top source directory. Don't try to run configure in this directory. Follow the configuration instructions in ../README. Please report bugs to "gcc-bugs@gcc.gnu.org" and send fixes to "gcc-patches@gcc.gnu.org". Thank you. ADDING A NEW FILE ================= There are two sets of files: Those that are "required" will be included in the library for all configurations, while those that are "optional" will be included in the library only if "needed." To add a new required file, edit Makefile.in to add the source file name to CFILES and the object file to REQUIRED_OFILES. To add a new optional file, it must provide a single function, and the name of the function must be the same as the name of the file. * Add the source file name to CFILES in Makefile.in and the object file to CONFIGURED_OFILES. * Add the function to name to the funcs shell variable in configure.ac. * Add the function to the AC_CHECK_FUNCS lists just after the setting of the funcs shell variable. These AC_CHECK_FUNCS calls are never executed; they are there to make autoheader work better. * Consider the special cases of building libiberty; as of this writing, the special cases are newlib and VxWorks. If a particular special case provides the function, you do not need to do anything. If it does not provide the function, add the object file to LIBOBJS, and add the function name to the case controlling whether to define HAVE_func. Finally, in the build directory of libiberty, configure with "--enable-maintainer-mode", run "make maint-deps" to update Makefile.in, and run 'make stamp-functions' to regenerate functions.texi. The optional file you've added (e.g. getcwd.c) should compile and work on all hosts where it is needed. It does not have to work or even compile on hosts where it is not needed. ADDING A NEW CONFIGURATION ========================== On most hosts you should be able to use the scheme for automatically figuring out which files are needed. In that case, you probably don't need a special Makefile stub for that configuration. If the fully automatic scheme doesn't work, you may be able to get by with defining EXTRA_OFILES in your Makefile stub. This is a list of object file names that should be treated as required for this configuration - they will be included in libiberty.a, regardless of whatever might be in the C library.