https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=4fa0265edea0940b865678d93749e224547dd36a

commit 4fa0265edea0940b865678d93749e224547dd36a
Author: Руслан Ижбулатов <lrn1986@gmail.com>
Date:   Thu Feb 28 10:25:41 2019 +0000

    Apply substitute-path to relative filenames as well
    
    When source file path is relative to the build directory (which
    is considered a good practice and is enforced in certain buildsystems,
    such as meson), gdb only applies substitute-path to the build directory
    path. Then gdb appends the source file path to the rewritten build
    directory path, and tries to access that.
    
    This fails if either two of the following conditions are true:
    a) The user didn't specify substitute-path for the build directory.
       This is highly likely, since path substitution for build directories
       is not documented anywhere, and since gdb does not tell[0] the user
       the path to the build directory, just the source file path.
    b) The source file path changed.
       This can also easily happen, since a source path that is relative
       to the build directory can include any number of directory names
       that are not part of the program source tree (starting with the
       name of the root directory of the source tree). Gdb will not apply
       substitute-path to that relative path, thus there is no way for
       the user to tell gdb about these changes.
    
    This commit changes the code to apply substitute-path to all filenames,
    both relative and absolute. This way it is possible to do things like:
    
    set substitute-path ../foobar-1.0 /src/my/foobar-1.0
    
    which is completely in line with the user expectations.
    
    This might break unusual cases where build directory path is also
    relative (is that even possible?) and happens to match the path
    to the source directory (i.e. happens to match a substitution rule).
    
    [0]: There's a "maintenance info symtabs" command that does show the names
         of the build directories, but normal users are not required to
         know or use that.
    
    gdb/ChangeLog
    2019-06-06  Руслан Ижбулатов <lrn1986@gmail.com>
    
    	* source.c (find_and_open_source): Also rewrite relative file
    	names.

Diff:
---
 gdb/ChangeLog |  5 +++++
 gdb/source.c  | 13 ++++---------
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 024e171..efe4618 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2019-06-06  Руслан Ижбулатов <lrn1986@gmail.com>
+
+	* source.c (find_and_open_source): Also rewrite relative file
+	names.
+
 2019-04-26  Amos Bird  <amosbird@gmail.com>
 
 	* annotate.c (annotate_thread_exited): Add "thread-exited"
diff --git a/gdb/source.c b/gdb/source.c
index 9a30209..00052e6 100644
--- a/gdb/source.c
+++ b/gdb/source.c
@@ -1025,16 +1025,11 @@ find_and_open_source (const char *filename,
 	}
     }
 
-  gdb::unique_xmalloc_ptr<char> rewritten_filename;
-  if (IS_ABSOLUTE_PATH (filename))
-    {
-      /* If filename is absolute path, try the source path
-	 substitution on it.  */
-      rewritten_filename = rewrite_source_path (filename);
+  gdb::unique_xmalloc_ptr<char> rewritten_filename
+    = rewrite_source_path (filename);
 
-      if (rewritten_filename != NULL)
-	filename = rewritten_filename.get ();
-    }
+  if (rewritten_filename != NULL)
+    filename = rewritten_filename.get ();
 
   result = openp (path, OPF_SEARCH_IN_PATH | OPF_RETURN_REALPATH, filename,
 		  OPEN_MODE, fullname);