* [committed] dwarf2out: reset generation count in toplev::finalize [PR98751]
@ 2021-01-20 1:01 David Malcolm
0 siblings, 0 replies; only message in thread
From: David Malcolm @ 2021-01-20 1:01 UTC (permalink / raw)
To: gcc-patches
PR debug/98751 reports an issue in which most of libgccjit's tests
fails in DWARF 5 handling with
`.Ldebug_loc2' is already defined"
asm errors.
The bogus label is being emitted at the 3rd in-process iteration, at:
31673 ASM_OUTPUT_LABEL (asm_out_file, loc_section_label);
which on the initial iteration emits:
145 │ .Ldebug_loc0:
on the 2nd iteration:
145 │ .Ldebug_loc1:
and on the 3rd iteration:
145 │ .Ldebug_loc2:
which is a duplicate of a label emitted earlier:
138 │ .section .debug_loclists,"",@progbits
139 │ .long .Ldebug_loc3-.Ldebug_loc2
140 │ .Ldebug_loc2:
141 │ .value 0x5
142 │ .byte 0x8
143 │ .byte 0
144 │ .long 0
145 │ .Ldebug_loc2:
The issue seems to be that init_sections_and_labels creates the label
ASM_GENERATE_INTERNAL_LABEL (loc_section_label, DEBUG_LOC_SECTION_LABEL,
generation);
where "generation" is a static local to init_sections_and_labels that
increments, and thus eventually hits the duplicate value.
It appears that this value is intended to be either 0 or 1, but in
the libgccjit case the compilation code can be invoked an arbitrary
number of times in-process, and hence can eventually lead to a
label name collision.
This patch adds code to dwarf2out_c_finalize (called by
toplev::finalize in libgccjit) to reset the generation counts,
fixing the issue.
Successfully bootstrapped & regrtested on x86_64-pc-linux-gnu.
Takes jit.sum from:
FAIL: 70->0 (-70)
PASS: 5734->11979 (+6245)
Given that Jakub independently came up with a near-identical patch
I've gone ahead and pushed this to master as
r11-6808-gb83604c75fee324cc4767d039178cba2fbbe017e.
gcc/ChangeLog:
PR debug/98751
* dwarf2out.c (output_line_info): Rename static variable
"generation", moving it out of the function to...
(output_line_info_generation): New.
(init_sections_and_labels): Likewise, renaming the variable to...
(init_sections_and_labels_generation): New.
(dwarf2out_c_finalize): Reset the new variables.
---
gcc/dwarf2out.c | 66 ++++++++++++++++++++++++++++++-------------------
1 file changed, 40 insertions(+), 26 deletions(-)
diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index 8b6890a5097..93e5d15e20a 100644
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -12709,22 +12709,27 @@ output_one_line_info_table (dw_line_info_table *table)
dw2_asm_output_data (1, DW_LNE_end_sequence, NULL);
}
+static unsigned int output_line_info_generation;
+
/* Output the source line number correspondence information. This
information goes into the .debug_line section. */
static void
output_line_info (bool prologue_only)
{
- static unsigned int generation;
char l1[MAX_ARTIFICIAL_LABEL_BYTES], l2[MAX_ARTIFICIAL_LABEL_BYTES];
char p1[MAX_ARTIFICIAL_LABEL_BYTES], p2[MAX_ARTIFICIAL_LABEL_BYTES];
bool saw_one = false;
int opc;
- ASM_GENERATE_INTERNAL_LABEL (l1, LINE_NUMBER_BEGIN_LABEL, generation);
- ASM_GENERATE_INTERNAL_LABEL (l2, LINE_NUMBER_END_LABEL, generation);
- ASM_GENERATE_INTERNAL_LABEL (p1, LN_PROLOG_AS_LABEL, generation);
- ASM_GENERATE_INTERNAL_LABEL (p2, LN_PROLOG_END_LABEL, generation++);
+ ASM_GENERATE_INTERNAL_LABEL (l1, LINE_NUMBER_BEGIN_LABEL,
+ output_line_info_generation);
+ ASM_GENERATE_INTERNAL_LABEL (l2, LINE_NUMBER_END_LABEL,
+ output_line_info_generation);
+ ASM_GENERATE_INTERNAL_LABEL (p1, LN_PROLOG_AS_LABEL,
+ output_line_info_generation);
+ ASM_GENERATE_INTERNAL_LABEL (p2, LN_PROLOG_END_LABEL,
+ output_line_info_generation++);
if (!XCOFF_DEBUGGING_INFO)
{
@@ -28589,6 +28594,10 @@ output_macinfo (const char *debug_line_label, bool early_lto_debug)
macinfo_label_base += macinfo_label_base_adj;
}
+/* As init_sections_and_labels may get called multiple times, have a
+ generation count for labels. */
+static unsigned init_sections_and_labels_generation;
+
/* Initialize the various sections and labels for dwarf output and prefix
them with PREFIX if non-NULL. Returns the generation (zero based
number of times function was called). */
@@ -28596,10 +28605,6 @@ output_macinfo (const char *debug_line_label, bool early_lto_debug)
static unsigned
init_sections_and_labels (bool early_lto_debug)
{
- /* As we may get called multiple times have a generation count for
- labels. */
- static unsigned generation = 0;
-
if (early_lto_debug)
{
if (!dwarf_split_debug_info)
@@ -28634,7 +28639,7 @@ init_sections_and_labels (bool early_lto_debug)
SECTION_DEBUG | SECTION_EXCLUDE, NULL);
ASM_GENERATE_INTERNAL_LABEL (debug_skeleton_abbrev_section_label,
DEBUG_SKELETON_ABBREV_SECTION_LABEL,
- generation);
+ init_sections_and_labels_generation);
/* Somewhat confusing detail: The skeleton_[abbrev|info] sections
stay in the main .o, but the skeleton_line goes into the split
@@ -28644,14 +28649,14 @@ init_sections_and_labels (bool early_lto_debug)
SECTION_DEBUG | SECTION_EXCLUDE, NULL);
ASM_GENERATE_INTERNAL_LABEL (debug_skeleton_line_section_label,
DEBUG_SKELETON_LINE_SECTION_LABEL,
- generation);
+ init_sections_and_labels_generation);
debug_str_offsets_section
= get_section (DEBUG_LTO_DWO_STR_OFFSETS_SECTION,
SECTION_DEBUG | SECTION_EXCLUDE,
NULL);
ASM_GENERATE_INTERNAL_LABEL (debug_skeleton_info_section_label,
DEBUG_SKELETON_INFO_SECTION_LABEL,
- generation);
+ init_sections_and_labels_generation);
debug_str_dwo_section = get_section (DEBUG_LTO_STR_DWO_SECTION,
DEBUG_STR_DWO_SECTION_FLAGS,
NULL);
@@ -28667,7 +28672,8 @@ init_sections_and_labels (bool early_lto_debug)
debug_line_section = get_section (DEBUG_LTO_LINE_SECTION,
SECTION_DEBUG | SECTION_EXCLUDE, NULL);
ASM_GENERATE_INTERNAL_LABEL (debug_line_section_label,
- DEBUG_LINE_SECTION_LABEL, generation);
+ DEBUG_LINE_SECTION_LABEL,
+ init_sections_and_labels_generation);
debug_str_section = get_section (DEBUG_LTO_STR_SECTION,
DEBUG_STR_SECTION_FLAGS
@@ -28711,7 +28717,7 @@ init_sections_and_labels (bool early_lto_debug)
SECTION_DEBUG, NULL);
ASM_GENERATE_INTERNAL_LABEL (debug_skeleton_abbrev_section_label,
DEBUG_SKELETON_ABBREV_SECTION_LABEL,
- generation);
+ init_sections_and_labels_generation);
/* Somewhat confusing detail: The skeleton_[abbrev|info] sections
stay in the main .o, but the skeleton_line goes into the
@@ -28721,13 +28727,13 @@ init_sections_and_labels (bool early_lto_debug)
SECTION_DEBUG | SECTION_EXCLUDE, NULL);
ASM_GENERATE_INTERNAL_LABEL (debug_skeleton_line_section_label,
DEBUG_SKELETON_LINE_SECTION_LABEL,
- generation);
+ init_sections_and_labels_generation);
debug_str_offsets_section
= get_section (DEBUG_DWO_STR_OFFSETS_SECTION,
SECTION_DEBUG | SECTION_EXCLUDE, NULL);
ASM_GENERATE_INTERNAL_LABEL (debug_skeleton_info_section_label,
DEBUG_SKELETON_INFO_SECTION_LABEL,
- generation);
+ init_sections_and_labels_generation);
debug_loc_section = get_section (dwarf_version >= 5
? DEBUG_DWO_LOCLISTS_SECTION
: DEBUG_DWO_LOC_SECTION,
@@ -28767,31 +28773,37 @@ init_sections_and_labels (bool early_lto_debug)
}
ASM_GENERATE_INTERNAL_LABEL (abbrev_section_label,
- DEBUG_ABBREV_SECTION_LABEL, generation);
+ DEBUG_ABBREV_SECTION_LABEL,
+ init_sections_and_labels_generation);
ASM_GENERATE_INTERNAL_LABEL (debug_info_section_label,
- DEBUG_INFO_SECTION_LABEL, generation);
+ DEBUG_INFO_SECTION_LABEL,
+ init_sections_and_labels_generation);
info_section_emitted = false;
ASM_GENERATE_INTERNAL_LABEL (debug_line_section_label,
- DEBUG_LINE_SECTION_LABEL, generation);
+ DEBUG_LINE_SECTION_LABEL,
+ init_sections_and_labels_generation);
/* There are up to 4 unique ranges labels per generation.
See also output_rnglists. */
ASM_GENERATE_INTERNAL_LABEL (ranges_section_label,
- DEBUG_RANGES_SECTION_LABEL, generation * 4);
+ DEBUG_RANGES_SECTION_LABEL,
+ init_sections_and_labels_generation * 4);
if (dwarf_version >= 5 && dwarf_split_debug_info)
ASM_GENERATE_INTERNAL_LABEL (ranges_base_label,
DEBUG_RANGES_SECTION_LABEL,
- 1 + generation * 4);
+ 1 + init_sections_and_labels_generation * 4);
ASM_GENERATE_INTERNAL_LABEL (debug_addr_section_label,
- DEBUG_ADDR_SECTION_LABEL, generation);
+ DEBUG_ADDR_SECTION_LABEL,
+ init_sections_and_labels_generation);
ASM_GENERATE_INTERNAL_LABEL (macinfo_section_label,
(dwarf_strict && dwarf_version < 5)
? DEBUG_MACINFO_SECTION_LABEL
- : DEBUG_MACRO_SECTION_LABEL, generation);
+ : DEBUG_MACRO_SECTION_LABEL,
+ init_sections_and_labels_generation);
ASM_GENERATE_INTERNAL_LABEL (loc_section_label, DEBUG_LOC_SECTION_LABEL,
- generation);
+ init_sections_and_labels_generation);
- ++generation;
- return generation - 1;
+ ++init_sections_and_labels_generation;
+ return init_sections_and_labels_generation - 1;
}
/* Set up for Dwarf output at the start of compilation. */
@@ -32379,6 +32391,8 @@ dwarf2out_c_finalize (void)
base_types.release ();
XDELETEVEC (producer_string);
producer_string = NULL;
+ output_line_info_generation = 0;
+ init_sections_and_labels_generation = 0;
}
#include "gt-dwarf2out.h"
--
2.26.2
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2021-01-20 1:01 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-01-20 1:01 [committed] dwarf2out: reset generation count in toplev::finalize [PR98751] David Malcolm
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).