[PATCH] libelf/elf_newscn.c: fix build failure against gcc-14 (-Walloc-size)

[Sergei Trofimovich]

`gcc-14` adde a new -Walloc-size warning that makes sure that size of an
individual element matches size of a pointed type:

https://gcc.gnu.org/PR71219

`elfutils` triggers is on `calloc()` call where member size is sued as
`1`.

elf_newscn.c: In function `elf_newscn`:
elf_newscn.c:97:12: error: allocation of insufficient size «1» for type 
«Elf_ScnList» with size «16» [-Werror=alloc-size]
   97 |   newp = calloc (sizeof (Elf_ScnList)
  |^

The change swaps arguments to pass larger value as a member size.

Signed-off-by: Sergei Trofimovich 
---
 libelf/elf_newscn.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/libelf/elf_newscn.c b/libelf/elf_newscn.c
index d6bdf153..ec731f75 100644
--- a/libelf/elf_newscn.c
+++ b/libelf/elf_newscn.c
@@ -94,9 +94,9 @@ elf_newscn (Elf *elf)
  1
 #endif
  )
-  newp = calloc (sizeof (Elf_ScnList)
-+ ((elf->state.elf.scnincr *= 2)
-   * sizeof (Elf_Scn)), 1);
+  newp = calloc (1, sizeof (Elf_ScnList)
+   + ((elf->state.elf.scnincr *= 2)
+  * sizeof (Elf_Scn)));
   if (newp == NULL)
{
  __libelf_seterrno (ELF_E_NOMEM);
-- 
2.42.0

[PATCH] tests: fix build against upcoming `gcc-14` (`-Werror=calloc-transposed-args`)

[Sergei Trofimovich]

`gcc-14` added a new `-Wcalloc-transposed-args` warning recently. It
detected minor infelicity in `calloc()` API usage in `elfutils`:

elfstrmerge.c: In function 'main':
elfstrmerge.c:450:32: error:
  'calloc' sizes specified with 'sizeof' in the earlier argument and not in 
the later argument [-Werror=calloc-transposed-args]
  450 |   newscnbufs = calloc (sizeof (void *), newshnums);
  |^~~~
elfstrmerge.c:450:32: note: earlier argument should specify number of 
elements, later size of each element

Signed-off-by: Sergei Trofimovich 
---
 tests/elfstrmerge.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/elfstrmerge.c b/tests/elfstrmerge.c
index 56350bb9..4eb58bbb 100644
--- a/tests/elfstrmerge.c
+++ b/tests/elfstrmerge.c
@@ -447,7 +447,7 @@ main (int argc, char **argv)
 }
 
   newshnums = shdrnum - 1;
-  newscnbufs = calloc (sizeof (void *), newshnums);
+  newscnbufs = calloc (newshnums, sizeof (void *));
   if (newscnbufs == NULL)
 fail_errno ("Couldn't allocate memory for new section buffers", NULL);
 
-- 
2.42.0

[PATCH] backends: allocate enough stace for null terminator

[Sergei Trofimovich]

`gcc-15` added a new warning in https://gcc.gnu.org/PR115185:

i386_regs.c:88:11: error: initializer-string for array of 'char' is too 
long [-Werror=unterminated-string-initialization]
   88 |   "ax", "cx", "dx", "bx", "sp", "bp", "si", "di", "ip"
  |   ^~~~

`elfutils` does not need to store '\0'. We could either initialize the
arrays with individual bytes or allocate extra byte for null.

This change allocates extra byte per string to fit in null terminator.

* backends/i386_regs.c (i386_register_info): Add extra byte per
    entry to fix gcc-15 warning.
* backends/x86_64_regs.c (x86_64_register_info): Ditto.

Signed-off-by: Sergei Trofimovich 
---
 backends/i386_regs.c   | 2 +-
 backends/x86_64_regs.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/backends/i386_regs.c b/backends/i386_regs.c
index 7ec93bb9..4bca1b1a 100644
--- a/backends/i386_regs.c
+++ b/backends/i386_regs.c
@@ -83,7 +83,7 @@ i386_register_info (Ebl *ebl __attribute__ ((unused)),
 
   switch (regno)
 {
-  static const char baseregs[][2] =
+  static const char baseregs[][3] =
{
  "ax", "cx", "dx", "bx", "sp", "bp", "si", "di", "ip"
};
diff --git a/backends/x86_64_regs.c b/backends/x86_64_regs.c
index ef987daf..c92c862a 100644
--- a/backends/x86_64_regs.c
+++ b/backends/x86_64_regs.c
@@ -80,7 +80,7 @@ x86_64_register_info (Ebl *ebl __attribute__ ((unused)),
 
   switch (regno)
 {
-  static const char baseregs[][2] =
+  static const char baseregs[][3] =
{
  "ax", "dx", "cx", "bx", "si", "di", "bp", "sp"
};
-- 
2.45.2

[PATCH v2] backends: allocate enough stace for null terminator

[Sergei Trofimovich]

`gcc-15` added a new warning in https://gcc.gnu.org/PR115185:

i386_regs.c:88:11: error: initializer-string for array of 'char' is too 
long [-Werror=unterminated-string-initialization]
   88 |   "ax", "cx", "dx", "bx", "sp", "bp", "si", "di", "ip"
  |   ^~~~

`elfutils` does not need to store '\0'. We could either initialize the
arrays with individual bytes or allocate extra byte for null.

This change initializes the array bytewise.

* backends/i386_regs.c (i386_register_info): Initialize the
array bytewise to fix gcc-15 warning.
* backends/x86_64_regs.c (x86_64_register_info): Ditto.

Signed-off-by: Sergei Trofimovich 
---
 backends/i386_regs.c   | 10 +-
 backends/x86_64_regs.c |  9 -
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/backends/i386_regs.c b/backends/i386_regs.c
index 7ec93bb9..ead55ef7 100644
--- a/backends/i386_regs.c
+++ b/backends/i386_regs.c
@@ -85,7 +85,15 @@ i386_register_info (Ebl *ebl __attribute__ ((unused)),
 {
   static const char baseregs[][2] =
{
- "ax", "cx", "dx", "bx", "sp", "bp", "si", "di", "ip"
+ {'a', 'x'},
+ {'c', 'x'},
+ {'d', 'x'},
+ {'b', 'x'},
+ {'s', 'p'},
+ {'b', 'p'},
+ {'s', 'i'},
+ {'d', 'i'},
+ {'i', 'p'},
};
 
 case 4:
diff --git a/backends/x86_64_regs.c b/backends/x86_64_regs.c
index ef987daf..dab8f27f 100644
--- a/backends/x86_64_regs.c
+++ b/backends/x86_64_regs.c
@@ -82,7 +82,14 @@ x86_64_register_info (Ebl *ebl __attribute__ ((unused)),
 {
   static const char baseregs[][2] =
{
- "ax", "dx", "cx", "bx", "si", "di", "bp", "sp"
+ {'a', 'x'},
+ {'d', 'x'},
+ {'c', 'x'},
+ {'b', 'x'},
+ {'s', 'i'},
+ {'d', 'i'},
+ {'b', 'p'},
+ {'s', 'p'},
};
 
 case 6 ... 7:
-- 
2.45.2

Re: [PATCH v2] backends: allocate enough stace for null terminator

[Sergei Trofimovich]

On Thu, 18 Jul 2024 18:49:54 +0200
Mark Wielaard  wrote:

> Hi Sergei,
> 
> On Wed, 2024-07-17 at 23:03 +0100, Sergei Trofimovich wrote:
> > `gcc-15` added a new warning in https://gcc.gnu.org/PR115185:
> > 
> > i386_regs.c:88:11: error: initializer-string for array of 'char' is too 
> > long [-Werror=unterminated-string-initialization]
> >88 |   "ax", "cx", "dx", "bx", "sp", "bp", "si", "di", "ip"
> >   |   ^~~~
> > 
> > `elfutils` does not need to store '\0'. We could either initialize the
> > arrays with individual bytes or allocate extra byte for null.
> > 
> > This change initializes the array bytewise.
> > 
> > * backends/i386_regs.c (i386_register_info): Initialize the
> > array bytewise to fix gcc-15 warning.
> > * backends/x86_64_regs.c (x86_64_register_info): Ditto.  
> 
> This looks good. I have pushed it to main.
> 
> Will this warning be enabled by -Wall or -Wextra (both of which are
> enabled by default for elfutils builds)? Or would be need to enable it
> explicitly?

Thank you! It's enabled only with `-Wextra` (and that's how I encountered
on build failure in `elfutils`).

-- 

  Sergei

Re: [PATCH v2] tests: do not fail on zero sized DIEs (binutils-2.39 compatible)

[Sergei Trofimovich via Elfutils-devel]

On Thu, 13 Oct 2022 16:40:36 +0200
Mark Wielaard  wrote:

> Hi,
> 
> On Mon, 2022-08-08 at 01:17 +0200, Mark Wielaard wrote:
> > On Sun, Aug 07, 2022 at 07:31:38PM +0100, Sergei Trofimovich via
> > Elfutils-devel wrote:  
> > > binutils started producing 0-sized DIEs on functions interspersed
> > > by nested sections (".section ...; .previous). This led to
> > > run-low_high_pc.sh failure in form of:
> > > 
> > > FAIL: run-low_high_pc.sh
> > > 
> > > 
> > > [b] main.c
> > > [2d] main
> > > 
> > > [b] ../sysdeps/i386/start.S
> > > [26] _start
> > > [40] ../sysdeps/x86/abi-note.c
> > > [b52] init.c
> > > [b8e] static-reloc.c
> > > [2dba] _dl_relocate_static_pie
> > > [2dd8] ../sysdeps/i386/crti.S
> > > [2def] _init
> > > lowpc: 8049000, highpc: 8049000lx
> > > ../sysdeps/i386/crti.S: [2def] '_init' highpc <= lowpc
> > > FAIL run-low_high_pc.sh (exit status: 255)
> > > 
> > > To work it around let's allow lowpc == highpc special case.
> > > 
> > > https://sourceware.org/bugzilla/show_bug.cgi?id=29450  
> > 
> > Thanks for finding this and suggesting a workaround.  But lets first
> > try to fix binutils. This seems like a pretty bad bug, lets hope it
> > gets fixed soon. So we don't need these kind of workarounds.
> > 
> > I added a comment to the binutils bug:
> > https://sourceware.org/bugzilla/show_bug.cgi?id=29451#c2  
> 
> Since this binutils bug was fixed I assume this patch isn't needed
> anymore.

Agreed. https://sourceware.org/PR29450#c8 cosed the bug as RESOLVED/MOVED
to declare it a binutils deficiency. Downstream use binutils-2.39 with a
gas patch and are able to run unmodified elfutils testsuite as is.

Thank you!

-- 

  Sergei

[PATCH] elfutils/configure.ac: use $READELF, not readelf

[Sergei Trofimovich via Elfutils-devel]

Allow user to specify own readelf. Use detected readelf,
not 'readelf'.

Noticed when was building elfutils on tuple-prefixed toolchain:

```
checking whether the compiler generates build-ids...
  ./configure: line 5197: readelf: command not found
no
```

Signed-off-by: Sergei Trofimovich 
---
 configure.ac | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index 74cc749d..8d3bcb7b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -200,7 +200,7 @@ fi
 # We really want build-ids. Warn and force generating them if gcc was
 # configure without --enable-linker-build-id
 AC_CACHE_CHECK([whether the compiler generates build-ids], ac_cv_buildid, [dnl
-AC_LINK_IFELSE([AC_LANG_PROGRAM()],[ac_cv_buildid=yes; readelf -n 
conftest$EXEEXT | grep -q NT_GNU_BUILD_ID || 
ac_cv_buildid=no],AC_MSG_FAILURE([unexpected compile failure]))])
+AC_LINK_IFELSE([AC_LANG_PROGRAM()],[ac_cv_buildid=yes; $READELF -n 
conftest$EXEEXT | grep -q NT_GNU_BUILD_ID || 
ac_cv_buildid=no],AC_MSG_FAILURE([unexpected compile failure]))])
 if test "$ac_cv_buildid" = "no"; then
AC_MSG_WARN([compiler doesn't generate build-id by default])
LDFLAGS="$LDFLAGS -Wl,--build-id"
-- 
2.27.0

[PATCH] src/elflint.c: add debug print for GNU_RETAIN and others

[Sergei Trofimovich via Elfutils-devel]

---
 src/elflint.c | 5 -
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/elflint.c b/src/elflint.c
index b3cbaade..7b7f7937 100644
--- a/src/elflint.c
+++ b/src/elflint.c
@@ -2789,7 +2789,10 @@ section_flags_string (GElf_Word flags, char *buf, size_t 
len)
   NEWFLAG (OS_NONCONFORMING),
   NEWFLAG (GROUP),
   NEWFLAG (TLS),
-  NEWFLAG (COMPRESSED)
+  NEWFLAG (COMPRESSED),
+  NEWFLAG (GNU_RETAIN),
+  NEWFLAG (ORDERED),
+  NEWFLAG (EXCLUDE)
 };
 #undef NEWFLAG
   const size_t nknown_flags = sizeof (known_flags) / sizeof (known_flags[0]);
-- 
2.30.0

[PATCH] src/elflint.c: fix printing of unknown flags

[Sergei Trofimovich via Elfutils-devel]

before the change section_flags_string() ignored unknown section
flags: snprintf() did write numeric value int obuffer, but
"*cp = '\0'" hegated the effect.

The change advances the 'cp' pointer'.

While at it add a '|' separator between known and unknown flags.

Signed-off-by: Sergei Trofimovich 
---
 src/elflint.c | 8 +---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/elflint.c b/src/elflint.c
index 7b7f7937..8f5227b3 100644
--- a/src/elflint.c
+++ b/src/elflint.c
@@ -2815,9 +2815,11 @@ section_flags_string (GElf_Word flags, char *buf, size_t 
len)
flags ^= known_flags[cnt].flag;
   }
 
-  if (flags != 0 || cp == buf)
-snprintf (cp, len - 1, "%" PRIx64, (uint64_t) flags);
-
+  if (flags != 0 || cp == buf) {
+int r = snprintf (cp, len - 1, "%s%" PRIx64, (cp == buf) ? "" : "|", 
(uint64_t) flags);
+if (r > 0)
+  cp += r;
+  }
   *cp = '\0';
 
   return buf;
-- 
2.30.0

Re: [PATCH] src/elflint.c: add debug print for GNU_RETAIN and others

[Sergei Trofimovich via Elfutils-devel]

On Tue, 12 Jan 2021 10:14:55 +0100
Mark Wielaard  wrote:

> Hi Sergei,
> 
> On Thu, 2020-12-31 at 12:11 +0000, Sergei Trofimovich via Elfutils-devel 
> wrote:
> > ---
> >  src/elflint.c | 5 -
> >  1 file changed, 4 insertions(+), 1 deletion(-)
> > 
> > diff --git a/src/elflint.c b/src/elflint.c
> > index b3cbaade..7b7f7937 100644
> > --- a/src/elflint.c
> > +++ b/src/elflint.c
> > @@ -2789,7 +2789,10 @@ section_flags_string (GElf_Word flags, char *buf, 
> > size_t len)
> >NEWFLAG (OS_NONCONFORMING),
> >NEWFLAG (GROUP),
> >NEWFLAG (TLS),
> > -  NEWFLAG (COMPRESSED)
> > +  NEWFLAG (COMPRESSED),
> > +  NEWFLAG (GNU_RETAIN),
> > +  NEWFLAG (ORDERED),
> > +  NEWFLAG (EXCLUDE)
> >  };
> >  #undef NEWFLAG
> >const size_t nknown_flags = sizeof (known_flags) / sizeof 
> > (known_flags[0]);  
> 
> Thanks, this is obviously correct and I pushed it. But normally a patch
> comes with a Signed-off-by line and a ChangeLog entry. I added both.
> But please see:
> https://sourceware.org/git/?p=elfutils.git;a=blob_plain;f=CONTRIBUTING;hb=HEAD

My apologies. Will follow CONTRIBUTING closer to future patches.

Thank you!

-- 

  Sergei

[PATCH] tests: use ${CC} instead of 'gcc' in tests

[Sergei Trofimovich via Elfutils-devel]

To better support cross-compilation Gentoo provides a way
to configure system without 'gcc' binary and only provide
tool-prefixed tools, like 'x86_64-pc-linux-gnu-gcc'.
The packages are built as ./configure --host=x86_64-pc-linux-gnu.

In https://bugs.gentoo.org/718872 Agostino Sarubbo found
a few test failures that use hardcoded 'gcc' instead of
expected ${CC}. The change propagates detected ${CC} at
configure time to test scripts.

Signed-off-by: Sergei Trofimovich 
---
 tests/ChangeLog| 10 ++
 tests/Makefile.am  |  6 --
 tests/run-disasm-x86-64.sh |  2 +-
 tests/run-disasm-x86.sh|  2 +-
 tests/run-strip-g.sh   |  2 +-
 tests/run-strip-nothing.sh |  2 +-
 tests/run-test-includes.sh | 14 +++---
 7 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/tests/ChangeLog b/tests/ChangeLog
index 3e5b630a..c6e9f618 100644
--- a/tests/ChangeLog
+++ b/tests/ChangeLog
@@ -1,3 +1,13 @@
+2021-01-31  Sergei Trofimovich  
+
+   * Makefile.am (TESTS_ENVIRONMENT): export CC variable
+   to tests for use instead of 'gcc'.
+   * run-disasm-x86-64.sh: use ${CC} instead of 'gcc'.
+   * run-disasm-x86.sh: Likewise.
+   * run-strip-g.sh: Likewise.
+   * run-strip-nothing.sh: Likewise.
+   * run-test-includes.sh: Likewise.
+
 2021-01-06  Timm Bäder  
 
* zstrptr.c (main): Lift print_strings function up to ...
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 502becff..c145720c 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -527,7 +527,8 @@ installed_TESTS_ENVIRONMENT = libdir=$(DESTDIR)$(libdir); \
  export libdir; export bindir; \
  export LC_ALL; export LANG; export VALGRIND_CMD; \
  unset DEBUGINFOD_URLS; \
- NM=$(NM); export NM;
+ NM=$(NM); export NM; \
+ CC=$(CC); export CC;
 installed_LOG_COMPILER = $(abs_srcdir)/test-wrapper.sh \
 installed $(tests_rpath) \
 '$(program_transform_name)'
@@ -538,7 +539,8 @@ TESTS_ENVIRONMENT = LC_ALL=C; LANG=C; 
VALGRIND_CMD=$(valgrind_cmd); \
export abs_top_builddir; \
export LC_ALL; export LANG; export VALGRIND_CMD; \
unset DEBUGINFOD_URLS; \
-   NM=$(NM); export NM;
+   NM=$(NM); export NM; \
+   CC=$(CC); export CC;
 LOG_COMPILER = $(abs_srcdir)/test-wrapper.sh \
   
$(abs_top_builddir)/libdw:$(abs_top_builddir)/backends:$(abs_top_builddir)/libelf:$(abs_top_builddir)/libasm:$(abs_top_builddir)/debuginfod
 
diff --git a/tests/run-disasm-x86-64.sh b/tests/run-disasm-x86-64.sh
index a6be62bb..07b612b0 100755
--- a/tests/run-disasm-x86-64.sh
+++ b/tests/run-disasm-x86-64.sh
@@ -22,7 +22,7 @@ case "`uname -m`" in
   x86_64)
 tempfiles testfile45.o
 testfiles testfile45.S testfile45.expect
-gcc -m64 -c -o testfile45.o testfile45.S
+${CC} -m64 -c -o testfile45.o testfile45.S
 testrun_compare ${abs_top_builddir}/src/objdump -d testfile45.o < 
testfile45.expect
 ;;
 esac
diff --git a/tests/run-disasm-x86.sh b/tests/run-disasm-x86.sh
index 28a3df74..7ac73ad7 100755
--- a/tests/run-disasm-x86.sh
+++ b/tests/run-disasm-x86.sh
@@ -22,7 +22,7 @@ case "`uname -m`" in
   x86_64 | i?86 )
 tempfiles testfile44.o
 testfiles testfile44.S testfile44.expect
-gcc -m32 -c -o testfile44.o testfile44.S
+${CC} -m32 -c -o testfile44.o testfile44.S
 testrun_compare ${abs_top_builddir}/src/objdump -d testfile44.o < 
testfile44.expect
 ;;
 esac
diff --git a/tests/run-strip-g.sh b/tests/run-strip-g.sh
index 13038195..15921215 100755
--- a/tests/run-strip-g.sh
+++ b/tests/run-strip-g.sh
@@ -25,7 +25,7 @@
 tempfiles a.out strip.out debug.out readelf.out
 
 echo Create debug a.out.
-echo "int main() { return 1; }" | gcc -g -xc -
+echo "int main() { return 1; }" | ${CC} -g -xc -
 
 echo strip -g to file with debug file
 testrun ${abs_top_builddir}/src/strip -g -o strip.out -f debug.out ||
diff --git a/tests/run-strip-nothing.sh b/tests/run-strip-nothing.sh
index 914fdfbf..710c200d 100755
--- a/tests/run-strip-nothing.sh
+++ b/tests/run-strip-nothing.sh
@@ -23,7 +23,7 @@
 tempfiles a.out strip.out debug.out
 
 # Create no-debug a.out.
-echo "int main() { return 1; }" | gcc -s -xc -
+echo "int main() { return 1; }" | ${CC} -s -xc -
 
 # strip to file
 testrun ${abs_top_builddir}/src/strip -g -o strip.out ||
diff --git a/tests/run-test-includes.sh b/tests/run-test-includes.sh
index b0ccdd9b..b107c6b9 100755
--- a/tests/run-test-includes.sh
+++ b/tests/run-test-includes.sh
@@ -3,24 +3,24 @@
 . $srcdir/test-subr.sh
 
 echo '#include "libelf.h"' \
-  | gcc -c -o /dev/null -I ${abs_srcdir

[PATCH] elflint: fix undefined 'buffer_left' reference

[Sergei Trofimovich via Elfutils-devel]

Link failure is reproducible on gcc-11.1.0 target:

```
$ autoreconf -i -f
$ ./configure --enable-maintainer-mode --disable-debuginfod \
--host=x86_64-pc-linux-gnu \
CFLAGS=-march=znver3 \
CXXFLAGS=-march=znver3 \
LDFLAGS=" "
$ make

  CCLD elflint
ld: elflint.o: in function `check_attributes':
elflint.c:(.text+0xdcff): undefined reference to `buffer_left'
ld: elflint.c:(.text+0xe557): undefined reference to `buffer_left'
```

It happens due to possible external linkage of `buffer_left()`.

The change forces local linkkage to always use local definition
(either inline or out-of-line).

Reported-by: Toralf Förster
Bug: https://bugs.gentoo.org/794601
Signed-off-by: Sergei Trofimovich 
---
 src/ChangeLog | 5 +
 src/elflint.c | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/ChangeLog b/src/ChangeLog
index 2c7be185..e030de0d 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2021-06-06  Sergei Trofimovich  
+
+   * elflint.c (buffer_left): Mark as 'inline' to avoid external linkage
+   failure.
+
 2021-05-12  Dmitry V. Levin  
 
* elfcompress.c (process_file): Return 1 instead of -1 in case of an
diff --git a/src/elflint.c b/src/elflint.c
index 85cc7833..35b40500 100644
--- a/src/elflint.c
+++ b/src/elflint.c
@@ -3434,7 +3434,7 @@ buffer_pos (Elf_Data *data, const unsigned char *p)
   return p - (const unsigned char *) data->d_buf;
 }
 
-inline size_t
+static inline size_t
 buffer_left (Elf_Data *data, const unsigned char *p)
 {
   return (const unsigned char *) data->d_buf + data->d_size - p;
-- 
2.31.1

[PATCH v2] elflint: fix undefined 'buffer_left' reference

[Sergei Trofimovich via Elfutils-devel]

Link failure is reproducible on gcc-11.1.0 target:

```
$ autoreconf -i -f
$ ./configure --enable-maintainer-mode --disable-debuginfod \
--host=x86_64-pc-linux-gnu \
CFLAGS=-march=znver3 \
CXXFLAGS=-march=znver3 \
LDFLAGS=" "
$ make

  CCLD elflint
ld: elflint.o: in function `check_attributes':
elflint.c:(.text+0xdcff): undefined reference to `buffer_left'
ld: elflint.c:(.text+0xe557): undefined reference to `buffer_left'
```

It happens due to possible external linkage of `buffer_left()`.

The change forces local linkkage to always use local definition
(either inline or out-of-line).

Reported-by: Toralf Förster
Bug: https://bugs.gentoo.org/794601
Signed-off-by: Sergei Trofimovich 
Fixes: e95d1fbb ("elflint: Pull left() in file scope")
---
Change since v1 suggested by Dmitry:
- fixed changelog to spell 'static' correctly :)
- added 'Fixes' annotation

Did not drop 'inline' to be consistent with other tiny helpers
in the same file.

 src/ChangeLog | 5 +
 src/elflint.c | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/ChangeLog b/src/ChangeLog
index 2c7be185..698b3c77 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2021-06-06  Sergei Trofimovich  
+
+   * elflint.c (buffer_left): Mark as 'static' to avoid external linkage
+   failure.
+
 2021-05-12  Dmitry V. Levin  
 
* elfcompress.c (process_file): Return 1 instead of -1 in case of an
diff --git a/src/elflint.c b/src/elflint.c
index 85cc7833..35b40500 100644
--- a/src/elflint.c
+++ b/src/elflint.c
@@ -3434,7 +3434,7 @@ buffer_pos (Elf_Data *data, const unsigned char *p)
   return p - (const unsigned char *) data->d_buf;
 }
 
-inline size_t
+static inline size_t
 buffer_left (Elf_Data *data, const unsigned char *p)
 {
   return (const unsigned char *) data->d_buf + data->d_size - p;
-- 
2.32.0

[PATCH] tests: do not fail on zero sized DIEs (binutils-2.39 compatible)

[Sergei Trofimovich via Elfutils-devel]

binutils started producing 0-sized DIEs on functions interspersed
by nested sections (".section ...; .previous). This led to
run-low_high_pc.sh failure in form of:

FAIL: run-low_high_pc.sh


[b] main.c
[2d] main

[b] ../sysdeps/i386/start.S
[26] _start
[40] ../sysdeps/x86/abi-note.c
[b52] init.c
[b8e] static-reloc.c
[2dba] _dl_relocate_static_pie
[2dd8] ../sysdeps/i386/crti.S
[2def] _init
lowpc: 8049000, highpc: 8049000lx
../sysdeps/i386/crti.S: [2def] '_init' highpc <= lowpc
FAIL run-low_high_pc.sh (exit status: 255)

To work it around let's allow lowpc == highpc special case.

https://sourceware.org/bugzilla/show_bug.cgi?id=29450

Signed-off-by: Sergei Trofimovich 
---
 tests/ChangeLog | 4 
 tests/low_high_pc.c | 3 +++
 2 files changed, 7 insertions(+)

diff --git a/tests/ChangeLog b/tests/ChangeLog
index 0c6f68ef..8296e0b6 100644
--- a/tests/ChangeLog
+++ b/tests/ChangeLog
@@ -1,3 +1,7 @@
+2022-08-04  Sergei Trofimovich  
+
+   * low_high_pc.c (handle_die): Allow zero sized DIEs for binutils-2.39.
+
 2022-08-01  Mark Wielaard  
 
* run-debuginfod-percent-escape.sh: Add initial scan wait_ready.
diff --git a/tests/low_high_pc.c b/tests/low_high_pc.c
index cd022b1c..80c83b6d 100644
--- a/tests/low_high_pc.c
+++ b/tests/low_high_pc.c
@@ -70,6 +70,9 @@ handle_die (Dwarf_Die *die, void *arg)
   if (dwarf_hasattr (die, DW_AT_low_pc)
   && dwarf_hasattr (die, DW_AT_high_pc)
   && highpc <= lowpc
+  /* gas-2.39 produces zero sized DIEs sometimes:
+ https://sourceware.org/PR29451.  */
+  && highpc != lowpc
   && ! (dwarf_tag (die) == DW_TAG_compile_unit && highpc == lowpc))
 {
   printf("lowpc: %" PRIx64 ", highpc: %" PRIx64 "\n", lowpc, highpc);
-- 
2.37.1

[PATCH] tests: run-low_high_pc.sh: drop redundant 'lx' suffix

[Sergei Trofimovich via Elfutils-devel]

Noticed when debugged test failure:

lowpc: 8049000, highpc: 8049000lx
../sysdeps/i386/crti.S: [2def] '_init' highpc <= lowpc

Signed-off-by: Sergei Trofimovich 
---
 tests/ChangeLog | 4 
 tests/low_high_pc.c | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/tests/ChangeLog b/tests/ChangeLog
index 0c6f68ef..d2952cc9 100644
--- a/tests/ChangeLog
+++ b/tests/ChangeLog
@@ -1,3 +1,7 @@
+2022-08-04  Sergei Trofimovich  
+
+   * low_high_pc.c (handle_die): Drop redundant 'lx' suffix.
+
 2022-08-01  Mark Wielaard  
 
* run-debuginfod-percent-escape.sh: Add initial scan wait_ready.
diff --git a/tests/low_high_pc.c b/tests/low_high_pc.c
index 78b6ad08..cd022b1c 100644
--- a/tests/low_high_pc.c
+++ b/tests/low_high_pc.c
@@ -72,7 +72,7 @@ handle_die (Dwarf_Die *die, void *arg)
   && highpc <= lowpc
   && ! (dwarf_tag (die) == DW_TAG_compile_unit && highpc == lowpc))
 {
-  printf("lowpc: %" PRIx64 ", highpc: %" PRIx64 "lx\n", lowpc, highpc);
+  printf("lowpc: %" PRIx64 ", highpc: %" PRIx64 "\n", lowpc, highpc);
   fail (off, name, "highpc <= lowpc");
 }
 
-- 
2.37.1

[PATCH v2] tests: do not fail on zero sized DIEs (binutils-2.39 compatible)

[Sergei Trofimovich via Elfutils-devel]

binutils started producing 0-sized DIEs on functions interspersed
by nested sections (".section ...; .previous). This led to
run-low_high_pc.sh failure in form of:

FAIL: run-low_high_pc.sh


[b] main.c
[2d] main

[b] ../sysdeps/i386/start.S
[26] _start
[40] ../sysdeps/x86/abi-note.c
[b52] init.c
[b8e] static-reloc.c
[2dba] _dl_relocate_static_pie
[2dd8] ../sysdeps/i386/crti.S
[2def] _init
lowpc: 8049000, highpc: 8049000lx
../sysdeps/i386/crti.S: [2def] '_init' highpc <= lowpc
FAIL run-low_high_pc.sh (exit status: 255)

To work it around let's allow lowpc == highpc special case.

https://sourceware.org/bugzilla/show_bug.cgi?id=29450

Signed-off-by: Sergei Trofimovich 
---
 tests/ChangeLog | 4 
 tests/low_high_pc.c | 8 +---
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/tests/ChangeLog b/tests/ChangeLog
index 0c6f68ef..59b4252a 100644
--- a/tests/ChangeLog
+++ b/tests/ChangeLog
@@ -1,3 +1,7 @@
+2022-08-07  Sergei Trofimovich  
+
+   * low_high_pc.c (handle_die): Allow zero sized DIEs for binutils-2.39.
+
 2022-08-01  Mark Wielaard  
 
* run-debuginfod-percent-escape.sh: Add initial scan wait_ready.
diff --git a/tests/low_high_pc.c b/tests/low_high_pc.c
index 78b6ad08..63268f4c 100644
--- a/tests/low_high_pc.c
+++ b/tests/low_high_pc.c
@@ -66,11 +66,13 @@ handle_die (Dwarf_Die *die, void *arg)
 fail (off, name, "has DW_AT_high_pc but dwarf_highpc fails");
 
   /* GCC < 4.7 had a bug where no code CUs got a highpc == lowpc.
- Allow that, because it is not the main purpose of this test.  */
+ Allow that, because it is not the main purpose of this test.
+ gas-2.39 produces zero sized DIEs for subprograms sometimes:
+ https://sourceware.org/PR29451.
+   */
   if (dwarf_hasattr (die, DW_AT_low_pc)
   && dwarf_hasattr (die, DW_AT_high_pc)
-  && highpc <= lowpc
-  && ! (dwarf_tag (die) == DW_TAG_compile_unit && highpc == lowpc))
+  && highpc < lowpc)
 {
   printf("lowpc: %" PRIx64 ", highpc: %" PRIx64 "lx\n", lowpc, highpc);
   fail (off, name, "highpc <= lowpc");
-- 
2.37.1