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[PATCH] libdw: Enable building with -Og.
- From: Mark Wielaard <mark at klomp dot org>
- To: elfutils-devel at sourceware dot org
- Cc: Mark Wielaard <mark at klomp dot org>
- Date: Fri, 23 Nov 2018 21:08:11 +0100
- Subject: [PATCH] libdw: Enable building with -Og.
When building with -Og gcc is unable to see that __libdw_dieabbrev ()
will initialize what the second argument points to when no error occurs
as called by dwarf_child and dwarf_getattrs. Causing an possibly
uninitialized error. Just initialize readp/die_addr to NULL, which is
the value we would return if an error occurs anyway.
https://sourceware.org/bugzilla/show_bug.cgi?id=23914
Signed-off-by: Mark Wielaard <mark@klomp.org>
---
libdw/ChangeLog | 5 +++++
libdw/dwarf_child.c | 2 +-
libdw/dwarf_getattrs.c | 2 +-
3 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/libdw/ChangeLog b/libdw/ChangeLog
index 7caa223..44405d7 100644
--- a/libdw/ChangeLog
+++ b/libdw/ChangeLog
@@ -1,3 +1,8 @@
+2018-10-23 Mark Wielaard <mark@klomp.org>
+
+ * dwarf_child.c (__libdw_find_attr): Initialize readp to NULL.
+ * dwarf_getattrs.c (dwarf_getattrs): Initialize die_addr to NULL.
+
2018-10-20 Mark Wielaard <mark@klomp.org>
* libdw.map (ELFUTILS_0.175): New section. Add dwelf_elf_begin.
diff --git a/libdw/dwarf_child.c b/libdw/dwarf_child.c
index 9446b88..2e39d83 100644
--- a/libdw/dwarf_child.c
+++ b/libdw/dwarf_child.c
@@ -43,7 +43,7 @@ internal_function
__libdw_find_attr (Dwarf_Die *die, unsigned int search_name,
unsigned int *codep, unsigned int *formp)
{
- const unsigned char *readp;
+ const unsigned char *readp = NULL;
/* Find the abbreviation entry. */
Dwarf_Abbrev *abbrevp = __libdw_dieabbrev (die, &readp);
diff --git a/libdw/dwarf_getattrs.c b/libdw/dwarf_getattrs.c
index 50faf98..4ac16b1 100644
--- a/libdw/dwarf_getattrs.c
+++ b/libdw/dwarf_getattrs.c
@@ -44,7 +44,7 @@ dwarf_getattrs (Dwarf_Die *die, int (*callback) (Dwarf_Attribute *, void *),
if (unlikely (offset == 1))
return 1;
- const unsigned char *die_addr;
+ const unsigned char *die_addr = NULL;
/* Find the abbreviation entry. */
Dwarf_Abbrev *abbrevp = __libdw_dieabbrev (die, &die_addr);
--
1.8.3.1