Hi,
On Wed, 2022-12-21 at 15:42 +0100, Mark Wielaard wrote:
>
> Unfortunately buildbot itself doesn't show the config.log.
> Trying to get that...
>
> configure:6961: checking for library containing ZSTD_compressStream2
> configure:6992: gcc -o conftest -D_FORTIFY_SOURCE=3 -g -O2
> -fsanitize=undefined
> -fno-sanitize-recover -fsanitize=address -fno-sanitize-
> recover conftest.c -llz
> ma -lbz2 >&5
> /usr/bin/ld: /tmp/ccKZnuYA.o: in function `main':
> /var/lib/buildbot/workers/wildebeest/elfutils-try-debian-
> armhf/build/conftest.c:
> 30: undefined reference to `ZSTD_compressStream2'
> collect2: error: ld returned 1 exit status
> configure:6992: $? = 1
> configure: failed program was:
> > /* confdefs.h */
> > #define PACKAGE_NAME "elfutils"
> > #define PACKAGE_TARNAME "elfutils"
> > #define PACKAGE_VERSION "0.188"
> > #define PACKAGE_STRING "elfutils 0.188"
> > #define PACKAGE_BUGREPORT "https://sourceware.org/bugzilla";
> > #define PACKAGE_URL "http://elfutils.org/";
> > #define PACKAGE "elfutils"
> > #define VERSION "0.188"
> > #define DEFAULT_AR_DETERMINISTIC false
> > #define HAVE_VISIBILITY 1
> > #define HAVE_STDATOMIC_H 1
> > #define _FILE_OFFSET_BITS 64
> > #define CHECK_UNDEFINED 1
> > #define USE_ZLIB 1
> > #define USE_BZLIB 1
> > #define USE_LZMA 1
> > /* end confdefs.h. */
> >
> > /* Override any GCC internal prototype to avoid an error.
> > Use char because int might match the return type of a GCC
> > builtin and then its argument prototype would still apply. */
> > #ifdef __cplusplus
> > extern "C"
> > #endif
> > char ZSTD_compressStream2 ();
> > int
> > main ()
> > {
> > return ZSTD_compressStream2 ();
> > ;
> > return 0;
> > }
>
> configure:6992: gcc -o conftest -D_FORTIFY_SOURCE=3 -g -O2
> -fsanitize=undefined
> -fno-sanitize-recover -fsanitize=address -fno-sanitize-
> recover conftest.c -lzs
> td -llzma -lbz2 >&5
> configure:6992: $? = 0
> configure:7009: result: -lzstd
>
> ehe? So it fails and then succeeds anyway?
>
> Strangely the same happens for the other compression library
> checks...
> lzma_auto_decoder and BZ2_bzdopen
>
> I don't fully understand this. Oddly the same seems to happen locally
> on my x86_64 box. So maybe the configure macros we have been using
> have
> always been bad/broken?
No, this is "normal". It first tries without the -l library (which is
the failing case) and then with the -l library (which succeeds).
What goes wrong is that this debian old stable arm setup has libzstd
containing a ZSTD_compressStream2 symbol...
40: 0000d349 264 FUNC GLOBAL DEFAULT 11 ZSTD_compressStream2
But the zstd.h header doesn't expose it...
/*******************************************************************************
*********
* ADVANCED AND EXPERIMENTAL FUNCTIONS
*******************************************************************************
*********
* The definitions in the following section are considered experimental.
* They are provided for advanced scenarios.
* They should never be used with a dynamic library, as prototypes may change in
the future.
* Use them only in association with static linking.
* *****************************************************************************
**********/
#if defined(ZSTD_STATIC_LINKING_ONLY) &&
!defined(ZSTD_H_ZSTD_STATIC_LINKING_ONLY)
...
grmbl.
This is somewhat unfortunate. We need a smarter configure check for this...
Cheers,
Mark
