Go to file
Mike Gulick f1b620e9b4 gdb: Look for compilation directory relative to directory search path
The 'directory' command allows the user to provide a list of filesystem
directories in which to search for source code.  The directories in this
search path are used as the base directory for the source filename from
the debug information (DW_AT_name).  Thus the directory search path
provides alternatives to the existing compilation directory from the
debug information (DW_AT_comp_dir).  Generally speaking, DW_AT_name
stores the filename argument passed to the compiler (including any
directory components), and DW_AT_comp_dir stores the current working
directory from which the compiler was executed.  For example:

    $ cd /path/to/project/subdir1
    $ gcc -c a/test.c -g

The corresponding debug information will look like this:

    DW_AT_name      : a/test.c
    DW_AT_comp_dir  : /path/to/project/subdir1

When compiling with the -fdebug-prefix-map GCC option, the compilation
directory can be arbitrarily rewritten.  In the above example, we may
rewrite the compilation directory as follows:

    $ gcc -c a/test.c -g -fdebug-prefix-map=/path/to/project=

In this case, the corresponding debug information will look like:

    DW_AT_name      : a/test.c
    DW_AT_comp_dir  : /subdir1

This prevents GDB from finding the corresponding source code based on
the debug information alone.  In some cases, a substitute-path command
can be used to re-map a consistent prefix in the rewritten compilation
directory to the real filesystem path.  However, there may not be a
consistent prefix remaining in the debug symbols (for example in a
project that has source code in many subdirectories under the project's
root), thereby requiring multiple substitute-path rules.  In this case,
it is easier to add the missing prefix to the directory search path via
the 'directory' command.

The function find_and_open_source currently searches in:

    SEARCH_PATH/FILENAME

where SEARCH_PATH corresponds to each individual entry in the directory
search path (which is guaranteed to contain the compilation directory
from the debug information, as well as the current working directory).
FILENAME corresponds to the source filename (DW_AT_name), which may have
directory components in it.  In addition, GDB searches in:

    SEARCH_PATH/FILE_BASENAME

where FILE_BASENAME is the basename of the DW_AT_name entry.

This change modifies find_and_open_source to additionally search in:

    SEARCH_PATH/COMP_DIR/FILENAME

where COMP_DIR is the compilation directory from the debug symbols.  In
the example given earlier, running:

    (gdb) directory /path/to/project

will now allow GDB to correctly locate the source code from the debug
information.

gdb/ChangeLog:

	* source.c (prepare_path_for_appending): New function.
	(openp): Make use of new function.
	(find_and_open_source): Search for the compilation directory and
	source file as a relative path beneath the directory search path.

gdb/doc/ChangeLog:

	* gdb.texinfo (Source Path): Additional text to better describe
	how the source path directory list is used when searching for
	source files.

gdb/testsuite/ChangeLog:

	* gdb.base/source-dir.exp: Add extra test for mapped compilation
	directory.
2019-09-17 16:20:19 -04:00
bfd Automatic date update in version.in 2019-09-17 00:00:47 +00:00
binutils Delete accidentally-checked in editor temporary file. 2019-09-16 11:03:53 +01:00
config Add markers for 2.33 branch to NEWS and ChangeLog files. 2019-09-09 10:27:40 +01:00
contrib Update dg-extract-results.* from gcc 2018-08-06 16:05:16 +02:00
cpu Add markers for 2.33 branch to NEWS and ChangeLog files. 2019-09-09 10:27:40 +01:00
elfcpp Add markers for 2.33 branch to NEWS and ChangeLog files. 2019-09-09 10:27:40 +01:00
etc Update year range in copyright notice of binutils files 2019-01-01 22:06:53 +10:30
gas Update version to 2.33.50 and regenerate configure scripts. 2019-09-16 11:03:53 +01:00
gdb gdb: Look for compilation directory relative to directory search path 2019-09-17 16:20:19 -04:00
gnulib Fix Gnulib glob.c resource leaks found by Coverity 2019-08-28 15:19:28 +01:00
gold Add markers for 2.33 branch to NEWS and ChangeLog files. 2019-09-09 10:27:40 +01:00
gprof Update version to 2.33.50 and regenerate configure scripts. 2019-09-16 11:03:53 +01:00
include Add markers for 2.33 branch to NEWS and ChangeLog files. 2019-09-09 10:27:40 +01:00
intl Change version to 2.32.51 and regenerate configure and pot files. 2019-01-19 16:51:42 +00:00
ld PR25002, ld/ldelf.c missing safe-ctype.h include 2019-09-16 23:51:48 +09:30
libctf Add markers for 2.33 branch to NEWS and ChangeLog files. 2019-09-09 10:27:40 +01:00
libdecnumber Merge config/ changes from GCC. 2018-10-31 17:16:41 +00:00
libiberty Synchronize libiberty sources with gcc mainline. 2019-08-09 16:16:18 +01:00
opcodes Update version to 2.33.50 and regenerate configure scripts. 2019-09-16 11:03:53 +01:00
readline [readline] Fix compilation on MinGW 2019-08-13 14:57:03 -05:00
sim bfd_get_filename 2019-09-06 12:22:59 +09:30
texinfo
zlib Merge config/ changes from GCC. 2018-10-31 17:16:41 +00:00
.cvsignore
.gitattributes
.gitignore Add archives and make stamps to the .gitignore file. 2016-09-27 15:10:42 +01:00
ar-lib Bump to autoconf 2.69 and automake 1.15.1 2018-06-19 16:55:06 -04:00
ChangeLog Add markers for 2.33 branch to NEWS and ChangeLog files. 2019-09-09 10:27:40 +01:00
compile
config-ml.in Update top level configure files by synchronizing them with gcc. 2018-01-10 15:29:21 +00:00
config.guess config.guess,config.sub: synchronize with config project master sources 2019-05-23 18:19:56 +02:00
config.rpath
config.sub config.guess,config.sub: synchronize with config project master sources 2019-05-23 18:19:56 +02:00
configure Add --with-static-standard-libraries to the top level 2019-08-19 10:17:11 -06:00
configure.ac Add --with-static-standard-libraries to the top level 2019-08-19 10:17:11 -06:00
COPYING
COPYING3
COPYING3.LIB
COPYING.LIB
COPYING.LIBGLOSS Update the address of the FSF in the copyright notice of files which were using the old address. 2017-12-14 12:48:55 +00:00
COPYING.NEWLIB
depcomp
djunpack.bat
install-sh
libtool.m4 Bump to autoconf 2.69 and automake 1.15.1 2018-06-19 16:55:06 -04:00
lt~obsolete.m4
ltgcc.m4
ltmain.sh
ltoptions.m4
ltsugar.m4
ltversion.m4
MAINTAINERS Move gnulib to top level 2019-06-14 12:40:02 -06:00
Makefile.def Move gnulib to top level 2019-06-14 12:40:02 -06:00
Makefile.in Move gnulib to top level 2019-06-14 12:40:02 -06:00
Makefile.tpl Revert "Sync top level files with versions from gcc." 2019-05-30 11:17:19 +01:00
makefile.vms
missing
mkdep
mkinstalldirs
move-if-change Update `move-if-change' from gnulib 2014-11-16 17:04:02 +01:00
multilib.am Merge autoconf / automake update changes from GCC. 2018-10-31 17:10:56 +00:00
README
README-maintainer-mode Bump to autoconf 2.69 and automake 1.15.1 2018-06-19 16:55:06 -04:00
setup.com
src-release.sh adjust src-release following the renaming of gdb/common/ to gdb/gdbsupport/ 2019-07-13 18:00:32 -07:00
symlink-tree
test-driver Bump to autoconf 2.69 and automake 1.15.1 2018-06-19 16:55:06 -04:00
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.