[patch-testcase] Re: RFC: Verify AT_ENTRY before using it

[Jan Kratochvil <jan dot kratochvil at redhat dot com>]

Hi,

just a patch on top of the in-reply-to one for more sanity checking.

It provides `set verbose' message which already exists for a long time in
LM_ADDR_CHECK (not info_verbose-conditioned until recently):
              if (info_verbose)
                {
                  warning (_(".dynamic section for \"%s\" "
                             "is not at the expected address"), so->so_name);
                  warning (_("difference appears to be caused by prelink, "
                             "adjusting expectations"));
                }

No regressions on {x86_64,x86_64-m32,i686}-fedora12-linux-gnu.

That quadruplication of `-re "Using PIE ...' block (4x2 similar blocks) is
ugly but AFAIK trying to make it more common faces TCL "uplevel" issues
already being solved complicated way in lib/gdb.exp proc gdb_test_multiple.


Thanks,
Jan


gdb/
2010-03-01  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* solib-svr4.c (svr4_exec_displacement):  Print DISPLACEMENT if
	INFO_VERBOSE.

gdb/testsuite/
2010-03-01  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* gdb.base/break-interp.exp: Create new displacement parameter value
	for the test_ld calls.
	(reach): New parameter displacement, verify its content.  New push of
	pf_prefix "reach-$func:".
	(test_core): New parameter displacement, verify its content.  New push
	of pf_prefix "core:".  New command "set verbose on".
	(test_attach): New parameter displacement, verify its content.  New
	push of pf_prefix "attach:".  New command "set verbose on".
	(test_ld): New parameter displacement, pass it to the reach, test_core
	and test_attach calls and verify its content in the "ld.so exit" test.

--- a/gdb/solib-svr4.c
+++ b/gdb/solib-svr4.c
@@ -1773,6 +1773,18 @@ svr4_exec_displacement (void)
 	}
     }
 
+  if (info_verbose)
+    {
+      /* It can be printed repeatedly as there is no easy way to check
+	 the executable symbols/file has been already relocated to
+	 displacement.  */
+
+      warning (_("Using PIE (Position Independent Executable) "
+		 "displacement %s for \"%s\""),
+	       paddress (target_gdbarch, displacement),
+	       bfd_get_filename (exec_bfd));
+    }
+
   return displacement;
 }
 
--- a/gdb/testsuite/gdb.base/break-interp.exp
+++ b/gdb/testsuite/gdb.base/break-interp.exp
@@ -221,12 +221,40 @@ proc strip_debug {dest} {
 }
 
 # `runto' does not check we stopped really at the function we specified.
-proc reach {func command} {
+# DISPLACEMENT can be "NONE", "ZERO" or "NONZERO"
+proc reach {func command displacement} {
     global gdb_prompt
 
+    global pf_prefix
+    set old_ldprefix $pf_prefix
+    lappend pf_prefix "reach-$func:"
+
     if [gdb_breakpoint $func allow-pending] {
-	set test "reach $func"
+	set test "reach"
+	set test_displacement "seen displacement message as $displacement"
 	gdb_test_multiple $command $test {
+	    -re "Using PIE \\(Position Independent Executable\\) displacement 0x0 " {
+		# Missing "$gdb_prompt $" is intentional.
+		if {$displacement == "ZERO"} {
+		    pass $test_displacement
+		    # Permit multiple such messages.
+		    set displacement "FOUND-$displacement"
+		} elseif {$displacement != "FOUND-ZERO"} {
+		    fail $test_displacement
+		}
+		exp_continue
+	    }
+	    -re "Using PIE \\(Position Independent Executable\\) displacement" {
+		# Missing "$gdb_prompt $" is intentional.
+		if {$displacement == "NONZERO"} {
+		    pass $test_displacement
+		    # Permit multiple such messages.
+		    set displacement "FOUND-$displacement"
+		} elseif {$displacement != "FOUND-NONZERO"} {
+		    fail $test_displacement
+		}
+		exp_continue
+	    }
 	    -re "Breakpoint \[0-9\]+, $func \\(.*\\) at .*:\[0-9\]+\r\n.*$gdb_prompt $" {
 		pass $test
 	    }
@@ -234,10 +262,15 @@ proc reach {func command} {
 		pass $test
 	    }
 	}
+	if ![regexp {^(NONE|FOUND-.*)$} $displacement] {
+	    fail $test_displacement
+	}
     }
+
+    set pf_prefix $old_ldprefix
 }
 
-proc test_core {file} {
+proc test_core {file displacement} {
     global srcdir subdir gdb_prompt
 
     set corefile [core_find $file {} "segv"]
@@ -245,6 +278,10 @@ proc test_core {file} {
 	return
     }
 
+    global pf_prefix
+    set old_ldprefix $pf_prefix
+    lappend pf_prefix "core:"
+
     gdb_exit
     gdb_start
     # Clear it to never find any separate debug infos in $debug_root.
@@ -252,14 +289,50 @@ proc test_core {file} {
     gdb_reinitialize_dir $srcdir/$subdir
     gdb_load $file
 
-    # Do not check the binary filename as it may be truncated.
-    gdb_test "core-file $corefile" "Core was generated by .*\r\n#0 .*" "core loaded"
+    # Print the "PIE (Position Independent Executable) displacement" message.
+    gdb_test "set verbose on"
+
+    set test "core loaded"
+    set test_displacement "seen displacement message"
+    gdb_test_multiple "core-file $corefile" $test {
+	-re "Using PIE \\(Position Independent Executable\\) displacement 0x0 " {
+	    # Missing "$gdb_prompt $" is intentional.
+	    if {$displacement == "ZERO"} {
+		pass $test_displacement
+		# Permit multiple such messages.
+		set displacement "FOUND-$displacement"
+	    } elseif {$displacement != "FOUND-ZERO"} {
+		fail $test_displacement
+	    }
+	    exp_continue
+	}
+	-re "Using PIE \\(Position Independent Executable\\) displacement" {
+	    # Missing "$gdb_prompt $" is intentional.
+	    if {$displacement == "NONZERO"} {
+		pass $test_displacement
+		# Permit multiple such messages.
+		set displacement "FOUND-$displacement"
+	    } elseif {$displacement != "FOUND-NONZERO"} {
+		fail $test_displacement
+	    }
+	    exp_continue
+	}
+	-re "Core was generated by .*\r\n#0 .*$gdb_prompt $" {
+	    # Do not check the binary filename as it may be truncated.
+	    pass $test
+	}
+    }
+    if ![regexp {^(NONE|FOUND-.*)$} $displacement] {
+	fail $test_displacement
+    }
 
     gdb_test "bt" "#\[0-9\]+ +\[^\r\n\]*\\mlibfunc\\M\[^\r\n\]*\r\n#\[0-9\]+ +\[^\r\n\]*\\mmain\\M.*" "core main bt"
+
+    set pf_prefix $old_ldprefix
 }
 
-proc test_attach {file} {
-    global board_info
+proc test_attach {file displacement} {
+    global board_info gdb_prompt
 
     gdb_exit
 
@@ -287,16 +360,66 @@ proc test_attach {file} {
 	}
     }
 
+    global pf_prefix
+    set old_ldprefix $pf_prefix
+    lappend pf_prefix "attach:"
+
     gdb_exit
     gdb_start
-    gdb_test "attach $pid" "Attaching to process $pid\r\n.*" "attach"
+
+    # Print the "PIE (Position Independent Executable) displacement" message.
+    gdb_test "set verbose on"
+
+    set test "attach"
+    gdb_test_multiple "attach $pid" $test {
+	-re "Attaching to process $pid\r\n" {
+	    # Missing "$gdb_prompt $" is intentional.
+	    pass $test
+	}
+    }
+
+    set test "attach final prompt"
+    set test_displacement "seen displacement message"
+    gdb_test_multiple "" $test {
+	-re "Using PIE \\(Position Independent Executable\\) displacement 0x0 " {
+	    # Missing "$gdb_prompt $" is intentional.
+	    if {$displacement == "ZERO"} {
+		pass $test_displacement
+		# Permit multiple such messages.
+		set displacement "FOUND-$displacement"
+	    } elseif {$displacement != "FOUND-ZERO"} {
+		fail $test_displacement
+	    }
+	    exp_continue
+	}
+	-re "Using PIE \\(Position Independent Executable\\) displacement" {
+	    # Missing "$gdb_prompt $" is intentional.
+	    if {$displacement == "NONZERO"} {
+		pass $test_displacement
+		# Permit multiple such messages.
+		set displacement "FOUND-$displacement"
+	    } elseif {$displacement != "FOUND-NONZERO"} {
+		fail $test_displacement
+	    }
+	    exp_continue
+	}
+	-re "$gdb_prompt $" {
+	    pass $test
+	}
+    }
+    if ![regexp {^(NONE|FOUND-.*)$} $displacement] {
+	fail $test_displacement
+    }
+
     gdb_test "bt" "#\[0-9\]+ +\[^\r\n\]*\\mlibfunc\\M\[^\r\n\]*\r\n#\[0-9\]+ +\[^\r\n\]*\\mmain\\M.*" "attach main bt"
     gdb_exit
 
     remote_exec host "kill -9 $pid"
+
+    set pf_prefix $old_ldprefix
 }
 
-proc test_ld {file ifmain trynosym} {
+proc test_ld {file ifmain trynosym displacement} {
     global srcdir subdir gdb_prompt
 
     # First test normal `file'-command loaded $FILE with symbols.
@@ -308,20 +431,25 @@ proc test_ld {file ifmain trynosym} {
     gdb_reinitialize_dir $srcdir/$subdir
     gdb_load $file
 
-    reach "dl_main" "run segv"
+    # Print the "PIE (Position Independent Executable) displacement" message.
+    gdb_test "set verbose on"
+
+    reach "dl_main" "run segv" $displacement
 
     gdb_test "bt" "#0 +\[^\r\n\]*\\mdl_main\\M.*" "dl bt"
 
     if $ifmain {
-	reach "main" continue
+	# Displacement message will be printed the second time on initializing
+	# the linker from svr4_special_symbol_handling.
+	reach "main" continue $displacement
 
-	reach "libfunc" continue
+	reach "libfunc" continue "NONE"
 
 	gdb_test "bt" "#0 +\[^\r\n\]*\\mlibfunc\\M\[^\r\n\]*\r\n#1 +\[^\r\n\]*\\mmain\\M.*" "main bt"
 
-	test_core $file
+	test_core $file $displacement
 
-	test_attach $file
+	test_attach $file $displacement
     }
 
     if !$trynosym {
@@ -341,12 +469,15 @@ proc test_ld {file ifmain trynosym} {
     gdb_test "set debug-file-directory"
     gdb_reinitialize_dir $srcdir/$subdir
 
+    # Print the "PIE (Position Independent Executable) displacement" message.
+    gdb_test "set verbose on"
+
     # Test no (error) message has been printed by `exec-file'.
     set escapedfile [string_to_regexp $file]
     gdb_test "exec-file $file" "exec-file $escapedfile" "load"
 
     if $ifmain {
-	reach "dl_main" run
+	reach "dl_main" run $displacement
 
 	set test "info files"
 	set entrynohex ""
@@ -363,7 +494,40 @@ proc test_ld {file ifmain trynosym} {
     } else {
 	# There is no symbol to break at ld.so.  Moreover it can exit with an
 	# error code.
-	gdb_test "run" "Program exited (normally|with code \[0-9\]+)\\." "ld.so exit"
+
+	set test "ld.so exit"
+	set test_displacement "seen displacement message"
+	gdb_test_multiple "run" $test {
+	    -re "Using PIE \\(Position Independent Executable\\) displacement 0x0 " {
+		# Missing "$gdb_prompt $" is intentional.
+		if {$displacement == "ZERO"} {
+		    pass $test_displacement
+		    # Permit multiple such messages.
+		    set displacement "FOUND-$displacement"
+		} elseif {$displacement != "FOUND-ZERO"} {
+		    fail $test_displacement
+		}
+		exp_continue
+	    }
+	    -re "Using PIE \\(Position Independent Executable\\) displacement" {
+		# Missing "$gdb_prompt $" is intentional.
+		if {$displacement == "NONZERO"} {
+		    pass $test_displacement
+		    # Permit multiple such messages.
+		    set displacement "FOUND-$displacement"
+		} elseif {$displacement != "FOUND-NONZERO"} {
+		    fail $test_displacement
+		}
+		exp_continue
+	    }
+	    -re "Program exited (normally|with code \[0-9\]+)\\.\r\n$gdb_prompt $" {
+		# Do not check the binary filename as it may be truncated.
+		pass $test
+	    }
+	}
+	if ![regexp {^(NONE|FOUND-.*)$} $displacement] {
+	    fail $test_displacement
+	}
     }
 
     set pf_prefix $old_ldprefix
@@ -450,7 +614,12 @@ foreach ldprelink {NO YES} {
 	if ![prelink$ldprelink $interp] {
 	    continue
 	}
-	test_ld $interp 0 [expr {$ldsepdebug == "NO"}]
+	if {$ldprelink == "NO"} {
+	    set displacement "NONZERO"
+	} else {
+	    set displacement "ZERO"
+	}
+	test_ld $interp 0 [expr {$ldsepdebug == "NO"}] $displacement
 
 	if ![copy $interp $interp_saved] {
 	    continue
@@ -531,7 +700,14 @@ foreach ldprelink {NO YES} {
 
 		    if {[prelink$binprelink "--dynamic-linker=$interp --ld-library-path=$dir $exec $interp [concat $dests]" [file tail $exec]]
 		        && [copy $interp_saved $interp]} {
-			test_ld $exec 1 [expr {$binsepdebug == "NO"}]
+			if {$binpie == "NO"} {
+			    set displacement "NONE"
+			} elseif {$binprelink == "NO"} {
+			    set displacement "NONZERO"
+			} else {
+			    set displacement "ZERO"
+			}
+			test_ld $exec 1 [expr {$binsepdebug == "NO"}] $displacement
 		    }
 		}
 	    }