gdb/testsuite: make gdb_gnu_strip_debug consistent

While writing a test I realised that the default behaviour of
gdb_gnu_strip_debug doesn't match its comment.

The comment says that the function takes a FILENAME, and splits the
file into FILENAME.stripped and FILENAME.debug, leaving FILENAME
unchanged.  The comment says that a .gnu_debuglink will be added to
FILENAME.stripped.

However, this is not true, FILENAME.stripped is created, with no debug
information.  FILENAME.debug is created containing the debug
information.

But, when adding the .gnu_debuglink we take FILENAME.stripped as the
input, and then overwrite FILENAME with the output.  As a result,
FILENAME.stripped does not include a .gnu_debuglink, while FILENAME
contains the .gnu_debuglink and no debug information!

The users of gdb_gnu_strip_debug can be split into two groups, those
who are using the .gnu_debuglink, these tests are all written assuming
that FILENAME is updated.

Then there are some tests that only rely on gdb_gnu_strip_debug's
ability to split out the debug information, these tests are then going
to do a lookup based on the build-id, these tests don't require the
.gnu_debuglink.  These tests use the FILENAME.stripped output file.

This all seems too confused to me.

As most uses of gdb_gnu_strip_debug assume that FILENAME is updated, I
propose that we just make that the actual, advertised behaviour of
this proc.

So now, gdb_gnu_strip_debug will take FILENAME, and will split the
debug information out into FILENAME.debug.  The debug information will
then be stripped from FILENAME, and by default a .gnu_debuglink will
be added to FILENAME pointing to FILENAME.debug.

I've updated the two tests that actually relied on FILENAME.stripped
to instead just use FILENAME.

One of the tests was doing a build-id based lookup, but was still
allowing the .gnu_debuglink to be added to FILENAME, I've updated this
test to pass the no-debuglink flag to gdb_gnu_strip_debug, which stops
the .gnu_debuglink from being added.

All of the tests that call gdb_gnu_strip_debug still pass for me.

Acked-By: Tom de Vries <tdevries@suse.de>

gdb/testsuite/gdb.base/corefile-buildid.exp

@@ -172,11 +172,9 @@ proc locate_exec_from_core_build_id {corefile buildid suffix \
 	"mkdir -p [file join $debugdir [file dirname $buildid]]"
 
     set files_list {}
+    lappend files_list $binfile $buildid
     if {$sepdebug} {
-	lappend files_list "$binfile.stripped" $buildid
 	lappend files_list "$binfile.debug" "$buildid.debug"
-    } else {
-	lappend files_list $binfile $buildid
     }
     if {$shared} {
 	global sharedir
@@ -200,12 +198,7 @@ proc locate_exec_from_core_build_id {corefile buildid suffix \
     gdb_test "core-file $corefile" "Program terminated with .*" \
 	"load core file"
     if {$symlink} {
-	if {$sepdebug} {
-	    set expected_file [file join $builddir \
-				   [file tail "$binfile.stripped"]]
-	} else {
-	    set expected_file [file join $builddir [file tail $binfile]]
-	}
+	set expected_file [file join $builddir [file tail $binfile]]
     } else {
 	set expected_file $buildid
     }
@@ -245,15 +238,12 @@ proc do_corefile_buildid_tests {args} {
 
     if {$sepdebug} {
 	# Strip debuginfo into its own file.
-	if {[gdb_gnu_strip_debug [standard_output_file $program_to_run]] \
-		!= 0} {
+	if {[gdb_gnu_strip_debug [standard_output_file $program_to_run] \
+		 no-debuglink] != 0} {
 	    untested "could not strip executable  for [join $suffix \ ]"
 	    return
 	}
 
-	# Run the stripped program instead of the original.
-	set program_to_run [file join $builddir \
-				[file tail "$binfile.stripped"]]
 	lappend suffix "sepdebug"
     }
 

gdb/testsuite/gdb.debuginfod/build-id-no-debug-warning.exp

@@ -30,14 +30,11 @@ if {[build_executable "build executable" ${testfile} ${srcfile} \
     return -1
 }
 
-# Split BINFILE into BINFILE.stripped and BINFILE.debug, the first is
-# the executable with the debug information removed, and the second is
-# the debug information.
+# Split debug information from BINFILE into BINFILE.debug.
 #
-# However, by passing the "no-debuglink" flag we prevent this proc
-# from adding a .gnu_debuglink section to the executable.  Any lookup
-# of the debug information by GDB will need to be done based on the
-# build-id.
+# By passing the "no-debuglink" flag we prevent this proc from adding
+# a .gnu_debuglink section to BINFILE.  Any lookup of the debug
+# information by GDB will need to be done based on the build-id.
 if {[gdb_gnu_strip_debug $binfile no-debuglink]} {
     unsupported "cannot produce separate debug info files"
     return -1
@@ -59,12 +56,6 @@ set debuginfod_debugdir [standard_output_file "debug"]
 remote_exec build "mkdir $debuginfod_debugdir"
 remote_exec build "mv $debugfile $debuginfod_debugdir"
 
-# This is BINFILE with the debug information removed.  We are going to
-# place this in the BUILD_ID_DEBUG_FILE location, this would usually
-# represent a mistake by the user, and will trigger a warning from
-# GDB, this is the warning we are checking for.
-set stripped_binfile [standard_output_file "${binfile}.stripped"]
-
 # Create the .build-id/PREFIX directory name from
 # .build-id/PREFIX/SUFFIX.debug filename.
 set debugdir [file dirname ${build_id_debug_file}]
@@ -76,7 +67,7 @@ remote_exec build "mkdir -p $debugdir"
 # information, which will point back at this file, which also doesn't
 # have debug information, which could cause a loop.  But GDB will spot
 # this and give a warning.
-remote_exec build "mv ${stripped_binfile} ${build_id_debug_file}"
+remote_exec build "mv ${binfile} ${build_id_debug_file}"
 
 # Now start GDB.
 clean_restart

gdb/testsuite/lib/gdb.exp

@@ -8057,10 +8057,11 @@ proc build_id_debug_filename_get { filename } {
 }
 
 # DEST should be a file compiled with debug information.  This proc
-# creates two new files DEST.debug which contains the debug
-# information extracted from DEST, and DEST.stripped, which is a copy
-# of DEST with the debug information removed.  A '.gnu_debuglink'
-# section will be added to DEST.stripped that points to DEST.debug.
+# creates DEST.debug which contains the debug information extracted
+# from DEST, and DEST is updated with the debug information removed.
+#
+# By default a '.gnu_debuglink' section will be added to DEST that
+# points to DEST.debug.
 #
 # If ARGS is passed, it is a list of optional flags.  The currently
 # supported flags are:
@@ -8068,7 +8069,7 @@ proc build_id_debug_filename_get { filename } {
 #   - no-main : remove the symbol entry for main from the separate
 #               debug file DEST.debug,
 #   - no-debuglink : don't add the '.gnu_debuglink' section to
-#                    DEST.stripped.
+#                    DEST.
 #
 # Function returns zero on success.  Function will return non-zero failure code
 # on some targets not supporting separate debug info (such as i386-msdos).
@@ -8127,20 +8128,26 @@ proc gdb_gnu_strip_debug { dest args } {
     # Unless the "no-debuglink" flag is passed, then link the two
     # previous output files together, adding the .gnu_debuglink
     # section to the stripped_file, containing a pointer to the
-    # debug_file, save the new file in dest.
+    # debug_file.
     if {[lsearch -exact $args "no-debuglink"] == -1} {
-	set result [catch "exec $objcopy_program --add-gnu-debuglink=${debug_file} ${stripped_file} ${dest}" output]
+	set result [catch "exec $objcopy_program --add-gnu-debuglink=${debug_file} ${stripped_file} ${stripped_file}-tmp" output]
 	verbose "result is $result"
 	verbose "output is $output"
 	if {$result == 1} {
 	    return 1
 	}
+	file delete "${stripped_file}"
+	file rename "${stripped_file}-tmp" "${stripped_file}"
     }
 
     # Workaround PR binutils/10802:
     # Preserve the 'x' bit also for PIEs (Position Independent Executables).
-    set perm [file attributes ${stripped_file} -permissions]
-    file attributes ${dest} -permissions $perm
+    set perm [file attributes ${dest} -permissions]
+    file attributes ${stripped_file} -permissions $perm
+
+    # Move the stripped_file back into dest.
+    file delete ${dest}
+    file rename ${stripped_file} ${dest}
 
     return 0
 }