Re: [PATCH] Fix possible alignment issue with dw2-dir-file-name test case

Pedro Alves
2014-01-10T16:39:00Z

On 01/10/2014 02:53 PM, Jan Kratochvil wrote:
> On Fri, 10 Jan 2014 15:30:46 +0100, Andreas Arnez wrote:
>> It's certainly simpler. Maybe Jan can explain why the functions had
>> been declared static?
>>
>> Your patch fixes the FAILs for me, so if there's no reason for the
>> static-ness, then I agree we should go with that.
>
> The Pedro's patch should be OK, there is nothing magic there.
>

Thanks.

On 01/10/2014 03:32 PM, Pedro Alves wrote:
> On 01/10/2014 02:30 PM, Andreas Arnez wrote:
>>
>> Your patch fixes the FAILs for me, so if there's no reason for the
>> static-ness, then I agree we should go with that.
>
> OK, I'll merge it with Andreas' commit log, and push it in in a sec.

(Eh, I had meant to send that as reply to Jan, but somehow managed
to botch it.)

Here's what I pushed.

--------
From: Andreas Arnez <arnez@linux.vnet.ibm.com>
Date: Fri, 10 Jan 2014 15:37:36 +0000
Subject: [PATCH] Since upstream gcc has recently increased the function
alignment on S390, the dw2-dir-file-name test case fails in
the first gdb_continue_to_breakpoint. Indeed, the
breakpoint is now placed into the alignment gap *before*
the actual function.

This happens because the test case declares the respective "*_start"
symbol as a "loose" label before the function definition, and the
compiler inserts the alignment between that label and the function
itself.

The "*_start" symbols were only necessary because FUNC made the
function static. The fix makes the functions extern instead, thus
making the "*_start" labels unnecessary.

testsuite/
2014-01-10 Andreas Arnez <arnez@linux.vnet.ibm.com>
Pedro Alves <palves@redhat.com>

* gdb.dwarf2/dw2-dir-file-name.c (FUNC): Remove "*_start" symbol.
Make "name" extern.
* gdb.dwarf2/dw2-dir-file-name.exp (out_cu, out_line): Replace
references to ${name}_start by references to ${name}.
---
gdb/testsuite/ChangeLog | 8 ++++++++
gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.c | 3 +--
gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp | 6 +++---
3 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 2bfeec1..904cca7 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2014-01-10 Andreas Arnez <arnez@linux.vnet.ibm.com>
+ Pedro Alves <palves@redhat.com>
+
+ * gdb.dwarf2/dw2-dir-file-name.c (FUNC): Remove "*_start" symbol.
+ Make "name" extern.
+ * gdb.dwarf2/dw2-dir-file-name.exp (out_cu, out_line): Replace
+ references to ${name}_start by references to ${name}.
+
2014-01-10 Joel Brobecker <brobecker@adacore.com>

* gdb.ada/pp-rec-component.exp: Remove path from "source" test.
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.c b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.c
index 21a4d2a..2b9cc6a 100644
--- a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.c
+++ b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.c
@@ -64,8 +64,7 @@ FUNC (compdir_absolute_ldir_absolute_file_absolute_same) \
FUNC (compdir_absolute_ldir_absolute_file_absolute_different)

#define FUNC(name) \
- asm (#name "_start: .globl " #name "_start\n"); \
- static void \
+ void \
name (void) \
{ \
v++; \
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp
index 7f29581..e523e89 100644
--- a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp
+++ b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp
@@ -54,7 +54,7 @@ proc out_cu { name cu_dir cu_name line_dir line_name } {
.ascii \"GNU C\\0\" /* DW_AT_producer */
.byte 2 /* DW_AT_language (DW_LANG_C) */
.4byte .Lline_${name}_begin /* DW_AT_stmt_list */
- .4byte ${name}_start /* DW_AT_low_pc */
+ .4byte ${name} /* DW_AT_low_pc */
.4byte ${name}_end /* DW_AT_high_pc */
"
if { $cu_dir != "" } {
@@ -65,7 +65,7 @@ proc out_cu { name cu_dir cu_name line_dir line_name } {

.uleb128 3 /* Abbrev: DW_TAG_subprogram */
.asciz \"${name}\" /* DW_AT_name */
- .4byte ${name}_start /* DW_AT_low_pc */
+ .4byte ${name} /* DW_AT_low_pc */
.4byte ${name}_end /* DW_AT_high_pc */

.byte 0 /* End of children of CU */
@@ -122,7 +122,7 @@ proc out_line { name cu_dir cu_name line_dir line_name } {
.byte 0 /* DW_LNE_set_address */
.uleb128 5
.byte 2
- .4byte ${name}_start
+ .4byte ${name}
.byte 1 /* DW_LNS_copy */
.byte 3 /* DW_LNS_advance_line */
.sleb128 1 /* ... to 1000 */
--
1.7.11.7