Modify dwarf_decl_file to support DW_AT_decl_file with value 0.
Because of inconsistencies in the DWARF 5 spec, it is ambiguous whether
DW_AT_decl_file value 0 is a valid .debug_line file table index for the
main source file or if it means that there is no source file specified.
dwarf_decl_file interprets DW_AT_decl_file 0 as meaning no source file
is specified. This works with DWARF 5 produced by gcc, which duplicates
the main source file name at index 0 and 1 of the file table and avoids
using DW_AT_decl_file 0.
However clang uses DW_AT_decl_file 0 for the main source index with no
duplication at another index. In this case dwarf_decl_file will be
unable to find the file name of the main file.
This patch changes dwarf_decl_file to treat DW_AT_decl_file 0 as a normal
index into the file table, allowing it to work with DWARF 5 debuginfo
produced by clang.
As for earlier DWARF versions which exclusively use DW_AT_decl_file 0
to indicate that no source file is specified, dwarf_decl_file will now
return the name "???" if called on a DIE with DW_AT_decl_file 0.
https://sourceware.org/bugzilla/show_bug.cgi?id=3
Signed-off-by: Aaron Merey
---
libdw/dwarf_decl_file.c | 25 ++---
tests/Makefile.am| 3 ++-
tests/run-allfcts.sh | 17 +
tests/testfile-dwarf5-line-clang.bz2 | Bin 0 -> 2764 bytes
4 files changed, 29 insertions(+), 16 deletions(-)
create mode 100755 tests/testfile-dwarf5-line-clang.bz2
diff --git a/libdw/dwarf_decl_file.c b/libdw/dwarf_decl_file.c
index 75662a33..07b69f8d 100644
--- a/libdw/dwarf_decl_file.c
+++ b/libdw/dwarf_decl_file.c
@@ -31,7 +31,6 @@
# include
#endif
-#include
#include
#include "libdwP.h"
@@ -48,13 +47,6 @@ dwarf_decl_file (Dwarf_Die *die)
&idx) != 0)
return NULL;
- /* Zero means no source file information available. */
- if (idx == 0)
-{
- __libdw_seterrno (DWARF_E_NO_ENTRY);
- return NULL;
-}
-
/* Get the array of source files for the CU. */
struct Dwarf_CU *cu = attr_mem.cu;
if (cu->lines == NULL)
@@ -63,20 +55,23 @@ dwarf_decl_file (Dwarf_Die *die)
size_t nlines;
/* Let the more generic function do the work. It'll create more
-data but that will be needed in an real program anyway. */
+data but that will be needed in a real program anyway. */
(void) INTUSE(dwarf_getsrclines) (&CUDIE (cu), &lines, &nlines);
- assert (cu->lines != NULL);
}
- if (cu->lines == (void *) -1l)
+ if (cu->lines == NULL || cu->lines == (void *) -1l)
{
- /* If the file index is not zero, there must be file information
-available. */
- __libdw_seterrno (DWARF_E_INVALID_DWARF);
+ /* Line table could not be found. */
return NULL;
}
- assert (cu->files != NULL && cu->files != (void *) -1l);
+ if (cu->files == NULL || cu->files == (void *) -1l)
+{
+ /* If the line table was found then then the file table should
+have also been found. */
+ __libdw_seterrno (DWARF_E_UNKNOWN_ERROR);
+ return NULL;
+}
if (idx >= cu->files->nfiles)
{
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 13bd9d56..b075e3c3 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -634,7 +634,8 @@ EXTRA_DIST = run-arextract.sh run-arsymtest.sh run-ar.sh \
testfile-largealign.o.bz2 run-strip-largealign.sh \
run-funcretval++11.sh \
test-ar-duplicates.a.bz2 \
-run-dwfl-core-noncontig.sh testcore-noncontig.bz2
+run-dwfl-core-noncontig.sh testcore-noncontig.bz2 \
+testfile-dwarf5-line-clang.bz2
if USE_VALGRIND
diff --git a/tests/run-allfcts.sh b/tests/run-allfcts.sh
index 9c0a55d8..1d4766fe 100755
--- a/tests/run-allfcts.sh
+++ b/tests/run-allfcts.sh
@@ -170,4 +170,21 @@ testrun_compare ${abs_builddir}/allfcts testfile-lto-gcc9
<<\EOF
/home/mark/src/tests/testfile-lto-main.c:6:main
EOF
+# = dwarf5-line.c =
+# int
+# main (int argc, char ** argv)
+# {
+# return 0;
+# }
+
+# Using clang version 17.0.4 (Fedora 17.0.4-1.fc39)
+# clang -gdwarf-5 -O0 -o testfile-dwarf5-line-clang dwarf5-line.c
+
+testfiles testfile-dwarf5-line-clang
+
+# Check that dwarf_decl_file can handle .debug_line file table index 0
+testrun_compare ${abs_builddir}/allfcts testfile-dwarf5-line-clang <<\EOF
+/home/amerey/test/dwarf5-line.c:2:main
+EOF
+
exit 0
diff --git a/tests/testfile-dwarf5-line-clang.bz2
b/tests/testfile-dwarf5-line-clang.bz2
new file mode 100755
index
..ab62b707bd7371268d6e685a2f86a1a3a868b0a9
GIT binary patch
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