Binutils with MCST patches
c973d0aa4a
(Ref: https://sourceware.org/ml/gdb/2017-06/msg00020.html) Assuming int_t is a typedef to int: typedef int int_t; gdb currently loses this expression's typedef: (gdb) p (int_t) 0 $1 = 0 (gdb) whatis $1 type = int or: (gdb) whatis (int_t) 0 type = int or, to get "whatis" out of the way: (gdb) maint print type (int_t) 0 ... name 'int' code 0x8 (TYPE_CODE_INT) ... This prevents a type printer for "int_t" kicking in, with e.g.: (gdb) p (int_t) 0 From the manual, we can see that that "whatis (int_t) 0" command invocation should have printed "type = int_t": If @var{arg} is a variable or an expression, @code{whatis} prints its literal type as it is used in the source code. If the type was defined using a @code{typedef}, @code{whatis} will @emph{not} print the data type underlying the @code{typedef}. (...) If @var{arg} is a type name that was defined using @code{typedef}, @code{whatis} @dfn{unrolls} only one level of that @code{typedef}. That one-level stripping is currently done here, in gdb/eval.c:evaluate_subexp_standard, handling OP_TYPE: ... else if (noside == EVAL_AVOID_SIDE_EFFECTS) { struct type *type = exp->elts[pc + 1].type; /* If this is a typedef, then find its immediate target. We use check_typedef to resolve stubs, but we ignore its result because we do not want to dig past all typedefs. */ check_typedef (type); if (TYPE_CODE (type) == TYPE_CODE_TYPEDEF) type = TYPE_TARGET_TYPE (type); return allocate_value (type); } However, this stripping is reachable in both: #1 - (gdb) whatis (int_t)0 # ARG is an expression with a cast to # typedef type. #2 - (gdb) whatis int_t # ARG is a type name. while only case #2 should strip the typedef. Removing that code from evaluate_subexp_standard is part of the fix. Instead, we make the "whatis" command implementation itself strip one level of typedefs when the command argument is a type name. We then run into another problem, also fixed by this commit: value_cast always drops any typedefs of the destination type. With all that fixed, "whatis (int_t) 0" now works as expected: (gdb) whatis int_t type = int (gdb) whatis (int_t)0 type = int_t value_cast has many different exit/convertion paths, for handling many different kinds of casts/conversions, and most of them had to be tweaked to construct the value of the right "to" type. The new tests try to exercise most of it, by trying castin of many different combinations of types. With: $ make check TESTS="*/whatis-ptype*.exp */gnu_vector.exp */dfp-test.exp" ... due to combinatorial explosion, the testsuite results for the tests above alone grow like: - # of expected passes 246 + # of expected passes 3811 You'll note that the tests exposed one GCC buglet, filed here: Missing DW_AT_type in DW_TAG_typedef of "typedef of typedef of void" https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81267 gdb/ChangeLog: 2017-08-21 Pedro Alves <palves@redhat.com> * eval.c (evaluate_subexp_standard) <OP_TYPE>: Don't dig past typedefs. * typeprint.c (whatis_exp): If handling "whatis", and expression is OP_TYPE, strip one typedef level. Otherwise don't strip typedefs here. * valops.c (value_cast): Save "to" type before resolving stubs/typedefs. Use that type as resulting value's type. gdb/testsuite/ChangeLog: 2017-08-21 Pedro Alves <palves@redhat.com> * gdb.base/dfp-test.c (d32_t, d64_t, d128_t, d32_t2, d64_t2, d128_t2, v_d32_t, v_d64_t) (v_d128_t, v_d32_t2, v_d64_t2, v_d128_t2): New. * gdb.base/dfp-test.exp: Add whatis/ptype/cast tests. * gdb.base/gnu_vector.exp: Add whatis/ptype/cast tests. * gdb.base/whatis-ptype-typedefs.c: New. * gdb.base/whatis-ptype-typedefs.exp: New. * gdb.python/py-prettyprint.c (int_type, int_type2): New typedefs. (an_int, an_int_type, an_int_type2): New globals. * gdb.python/py-prettyprint.exp (run_lang_tests): Add tests involving typedefs and cast expressions. * gdb.python/py-prettyprint.py (class pp_int_typedef): New. (lookup_typedefs_function): New. (typedefs_pretty_printers_dict): New. (top level): Register lookup_typedefs_function in gdb.pretty_printers. |
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| bfd | ||
| binutils | ||
| config | ||
| cpu | ||
| elfcpp | ||
| etc | ||
| gas | ||
| gdb | ||
| gold | ||
| gprof | ||
| include | ||
| intl | ||
| ld | ||
| libdecnumber | ||
| libiberty | ||
| opcodes | ||
| readline | ||
| sim | ||
| texinfo | ||
| zlib | ||
| .cvsignore | ||
| .gitattributes | ||
| .gitignore | ||
| ChangeLog | ||
| compile | ||
| config-ml.in | ||
| config.guess | ||
| config.rpath | ||
| config.sub | ||
| configure | ||
| configure.ac | ||
| COPYING | ||
| COPYING3 | ||
| COPYING3.LIB | ||
| COPYING.LIB | ||
| COPYING.LIBGLOSS | ||
| COPYING.NEWLIB | ||
| depcomp | ||
| djunpack.bat | ||
| install-sh | ||
| libtool.m4 | ||
| lt~obsolete.m4 | ||
| ltgcc.m4 | ||
| ltmain.sh | ||
| ltoptions.m4 | ||
| ltsugar.m4 | ||
| ltversion.m4 | ||
| MAINTAINERS | ||
| Makefile.def | ||
| Makefile.in | ||
| Makefile.tpl | ||
| makefile.vms | ||
| missing | ||
| mkdep | ||
| mkinstalldirs | ||
| move-if-change | ||
| README | ||
| README-maintainer-mode | ||
| setup.com | ||
| src-release.sh | ||
| symlink-tree | ||
| ylwrap | ||
README for GNU development tools This directory contains various GNU compilers, assemblers, linkers, debuggers, etc., plus their support routines, definitions, and documentation. If you are receiving this as part of a GDB release, see the file gdb/README. If with a binutils release, see binutils/README; if with a libg++ release, see libg++/README, etc. That'll give you info about this package -- supported targets, how to use it, how to report bugs, etc. It is now possible to automatically configure and build a variety of tools with one command. To build all of the tools contained herein, run the ``configure'' script here, e.g.: ./configure make To install them (by default in /usr/local/bin, /usr/local/lib, etc), then do: make install (If the configure script can't determine your type of computer, give it the name as an argument, for instance ``./configure sun4''. You can use the script ``config.sub'' to test whether a name is recognized; if it is, config.sub translates it to a triplet specifying CPU, vendor, and OS.) If you have more than one compiler on your system, it is often best to explicitly set CC in the environment before running configure, and to also set CC when running make. For example (assuming sh/bash/ksh): CC=gcc ./configure make A similar example using csh: setenv CC gcc ./configure make Much of the code and documentation enclosed is copyright by the Free Software Foundation, Inc. See the file COPYING or COPYING.LIB in the various directories, for a description of the GNU General Public License terms under which you can copy the files. REPORTING BUGS: Again, see gdb/README, binutils/README, etc., for info on where and how to report problems.