On Fri, Sep 30, 2016 at 07:07:22PM +0200, Jan-Benedict Glaw wrote:
> When building for --target=sparc-leon-elf (using config-list.mk) with
> a current GCC, I get this error message (cf.
> http://toolchain.lug-owl.de/buildbot/show_build_details.php?id=632317):
>
> g++ -fno-PIE -c -g -O2 -DIN_GCC -DCROSS_DIRECTORY_STRUCTURE
> -fno-exceptions -fno-rtti -fasynchronous-unwind-tables -W -Wall
> -Wno-narrowing -Wwrite-strings -Wcast-qual -Wmissing-format-attribute
> -Woverloaded-virtual -pedantic -Wno-long-long -Wno-variadic-macros
> -Wno-overlength-strings -Werror -fno-common -DHAVE_CONFIG_H -I. -I.
> -I/home/jbglaw/repos-configlist_mk/gcc/gcc
> -I/home/jbglaw/repos-configlist_mk/gcc/gcc/.
> -I/home/jbglaw/repos-configlist_mk/gcc/gcc/../include
> -I/home/jbglaw/repos-configlist_mk/gcc/gcc/../libcpp/include
> -I/opt/cfarm/mpc/include
> -I/home/jbglaw/repos-configlist_mk/gcc/gcc/../libdecnumber
> -I/home/jbglaw/repos-configlist_mk/gcc/gcc/../libdecnumber/dpd
> -I../libdecnumber -I/home/jbglaw/repos-configlist_mk/gcc/gcc/../libbacktrace
> -o dwarf2out.o -MT dwarf2out.o -MMD -MP -MF ./.deps/dwarf2out.TPo
> /home/jbglaw/repos-configlist_mk/gcc/gcc/dwarf2out.c
> /home/jbglaw/repos-configlist_mk/gcc/gcc/dwarf2out.c: In function ‘void
> dwarf2out_do_cfi_startproc(bool)’:
> /home/jbglaw/repos-configlist_mk/gcc/gcc/dwarf2out.c:942:1: error: may write
> a terminating nul past the end of the destination [-Werror=format-length=]
> dwarf2out_do_cfi_startproc (bool second)
> ^~~~~~~~~~~~~~~~~~~~~~~~~~
> /home/jbglaw/repos-configlist_mk/gcc/gcc/dwarf2out.c:973:36: note: format
> output between 10 and 21 bytes into a destination of size 20
> current_function_funcdef_no);
> ^
> cc1plus: all warnings being treated as errors
> Makefile:1102: recipe for target 'dwarf2out.o' failed
>
> I haven't really tracked down since when that error/warning shows up
> and whether or not it's valid, but maybe you might want to have a look?
I think sparc-leon-elf uses "*.L%s%ld" format, so for string of length 6
and int cast to long int it needs theoretically up to 21 bytes (3 + 6 + 11 + 1)
byt that would only trigger if the counters overflow from INT_MAX to
INT_MIN (so wouldn't be valid assembly anyway).
That said, most of spots in dwarf2out.c use the MAX_ARTIFICIAL_LABEL_BYTES
macro for sizing such buffers, so instead of changing the [20] to [21] if
the prefix can be 6 bytes I think it is cleaner to switch to using that
macro everywhere.
Ok if it passes bootstrap/regtest?
2016-09-30 Jakub Jelinek <ja...@redhat.com>
* dwarf2out.c (output_fde, output_call_frame_info,
dwarf2out_do_cfi_startproc, set_indirect_string,
gen_internal_sym, output_die, output_line_info): Use
MAX_ARTIFICIAL_LABEL_BYTES as char array sizes for
ASM_GENERATE_INTERNAL_LABEL output.
--- gcc/dwarf2out.c.jj 2016-09-29 22:53:14.000000000 +0200
+++ gcc/dwarf2out.c 2016-09-30 20:41:00.839532467 +0200
@@ -567,7 +567,7 @@ output_fde (dw_fde_ref fde, bool for_eh,
{
const char *begin, *end;
static unsigned int j;
- char l1[20], l2[20];
+ char l1[MAX_ARTIFICIAL_LABEL_BYTES], l2[MAX_ARTIFICIAL_LABEL_BYTES];
targetm.asm_out.emit_unwind_label (asm_out_file, fde->decl, for_eh,
/* empty */ 0);
@@ -722,7 +722,8 @@ output_call_frame_info (int for_eh)
unsigned int i;
dw_fde_ref fde;
dw_cfi_ref cfi;
- char l1[20], l2[20], section_start_label[20];
+ char l1[MAX_ARTIFICIAL_LABEL_BYTES], l2[MAX_ARTIFICIAL_LABEL_BYTES];
+ char section_start_label[MAX_ARTIFICIAL_LABEL_BYTES];
bool any_lsda_needed = false;
char augmentation[6];
int augmentation_size;
@@ -966,7 +967,7 @@ dwarf2out_do_cfi_startproc (bool second)
if (crtl->uses_eh_lsda)
{
- char lab[20];
+ char lab[MAX_ARTIFICIAL_LABEL_BYTES];
enc = ASM_PREFERRED_EH_DATA_FORMAT (/*code=*/0, /*global=*/0);
ASM_GENERATE_INTERNAL_LABEL (lab, second ? "LLSDAC" : "LLSDA",
@@ -4128,7 +4129,7 @@ AT_string (dw_attr_node *a)
static void
set_indirect_string (struct indirect_string_node *node)
{
- char label[32];
+ char label[MAX_ARTIFICIAL_LABEL_BYTES];
/* Already indirect is a no op. */
if (node->form == DW_FORM_strp || node->form == DW_FORM_GNU_str_index)
{
@@ -7076,7 +7077,7 @@ is_template_instantiation (dw_die_ref di
static char *
gen_internal_sym (const char *prefix)
{
- char buf[256];
+ char buf[MAX_ARTIFICIAL_LABEL_BYTES];
ASM_GENERATE_INTERNAL_LABEL (buf, prefix, label_num++);
return xstrdup (buf);
@@ -9382,7 +9383,7 @@ output_die (dw_die_ref die)
case dw_val_class_fde_ref:
{
- char l1[20];
+ char l1[MAX_ARTIFICIAL_LABEL_BYTES];
ASM_GENERATE_INTERNAL_LABEL (l1, FDE_LABEL,
a->dw_attr_val.v.val_fde_index * 2);
@@ -10710,7 +10711,8 @@ output_one_line_info_table (dw_line_info
static void
output_line_info (bool prologue_only)
{
- char l1[20], l2[20], p1[20], p2[20];
+ char l1[MAX_ARTIFICIAL_LABEL_BYTES], l2[MAX_ARTIFICIAL_LABEL_BYTES];
+ char p1[MAX_ARTIFICIAL_LABEL_BYTES], p2[MAX_ARTIFICIAL_LABEL_BYTES];
/* We don't support DWARFv5 line tables yet. */
int ver = dwarf_version < 5 ? dwarf_version : 4;
bool saw_one = false;
Jakub
