Bug#841624: libcdio: FTBFS: ../../include/cdio/iso9660.h:277:45: error: flexible array member 'iso9660_dir_s::filename' not at end of 'struct iso9660_pvd_s'

[Andreas Metzler]

On 2016-10-21 Lucas Nussbaum  wrote:
> Source: libcdio
> Version: 0.83-4.2
> Severity: serious
> Tags: stretch sid
> User: debian...@lists.debian.org
> Usertags: qa-ftbfs-20161021 qa-ftbfs
> Justification: FTBFS on amd64

> Hi,

> During a rebuild of all packages in sid, your package failed to build on
> amd64.
[...]


This seems to be fixed in experimental's 0.92. Afaict this was fixed in
http://git.savannah.gnu.org/gitweb/?p=libcdio.git;a=commitdiff;h=0bdb015d47b95abaa79fc2b83ffacdd63429a992
with
diff --git a/include/cdio/iso9660.h b/include/cdio/iso9660.h
index 45ece74..942c52d 100644 (file)
--- a/include/cdio/iso9660.h
+++ b/include/cdio/iso9660.h
@@ -60,7 +60,7 @@ typedef uint64_t iso733_t; /*! See section 7.3.3 */
 typedef char achar_t;  /*! See section 7.4.1 */
 typedef char dchar_t;  /*! See section 7.4.1 */
 
-#ifndef  EMPTY_ARRAY_SIZE
+#ifndef EMPTY_ARRAY_SIZE
 #define EMPTY_ARRAY_SIZE 0
 #endif
 
@@ -273,8 +273,18 @@ struct iso9660_dir_s {
   the Extent described by this
   Directory Record is
   recorded. (9.1.9) */
-  iso711_t filename_len;  /*! number of bytes in filename field */
-  char filename[EMPTY_ARRAY_SIZE];
+/*! MSVC compilers cannot handle a zero sized array in the middle
+of a struct, and iso9660_dir_s is reused within iso9660_pvd_s.
+Therefore, instead of defining:
+   iso711_t filename_len;
+   char filename[];
+we leverage the fact that iso711_t and char are the same size
+and use an union. The only gotcha is that the actual string
+payload of filename.str[] starts at 1, not 0. */
+  union { 
+iso711_tlen;
+charstr[1];
+  } filename;
 } GNUC_PACKED;
 
 /*! 

and the related changes.

cu Andreas

-- 
`What a good friend you are to him, Dr. Maturin. His other friends are
so grateful to you.'
`I sew his ears on from time to time, sure'

Bug#841624: libcdio: FTBFS: ../../include/cdio/iso9660.h:277:45: error: flexible array member 'iso9660_dir_s::filename' not at end of 'struct iso9660_pvd_s'

[Lucas Nussbaum]

Source: libcdio
Version: 0.83-4.2
Severity: serious
Tags: stretch sid
User: debian...@lists.debian.org
Usertags: qa-ftbfs-20161021 qa-ftbfs
Justification: FTBFS on amd64

Hi,

During a rebuild of all packages in sid, your package failed to build on
amd64.

Relevant part (hopefully):
> /bin/bash ../../libtool  --tag=CXX   --mode=compile x86_64-linux-gnu-g++ 
> -DHAVE_CONFIG_H -I. -I../.. -I../../include/ -I../../include-g -O2 -MT 
> iso9660.lo -MD -MP -MF .deps/iso9660.Tpo -c -o iso9660.lo iso9660.cpp
> libtool: compile:  x86_64-linux-gnu-g++ -DHAVE_CONFIG_H -I. -I../.. 
> -I../../include/ -I../../include -g -O2 -MT iso9660.lo -MD -MP -MF 
> .deps/iso9660.Tpo -c iso9660.cpp  -fPIC -DPIC -o .libs/iso9660.o
> In file included from ../../include/cdio++/iso9660.hpp:27:0,
>  from iso9660.cpp:27:
> ../../include/cdio/iso9660.h:277:45: error: flexible array member 
> 'iso9660_dir_s::filename' not at end of 'struct iso9660_pvd_s'
>char filename[EMPTY_ARRAY_SIZE];
>  ^
> ../../include/cdio/iso9660.h:310:20: note: next member 'char 
> iso9660_pvd_s::root_directory_filename' declared here
>char root_directory_filename;  /**< Is '\\0' or root
> ^~~
> ../../include/cdio/iso9660.h:283:8: note: in the definition of 'struct 
> iso9660_pvd_s'
>  struct iso9660_pvd_s {
> ^
> ../../include/cdio/iso9660.h:277:45: error: flexible array member 
> 'iso9660_dir_s::filename' not at end of 'struct iso9660_svd_s'
>char filename[EMPTY_ARRAY_SIZE];
>  ^
> ../../include/cdio/iso9660.h:424:20: note: next member 'char 
> iso9660_svd_s::root_directory_filename' declared here
>char root_directory_filename;  /**< Is '\\0' or root
> ^~~
> ../../include/cdio/iso9660.h:392:8: note: in the definition of 'struct 
> iso9660_svd_s'
>  struct iso9660_svd_s {
> ^
> ../../include/cdio/iso9660.h:277:45: error: flexible array member 
> 'iso9660_dir_s::filename' not at end of 'class ISO9660::PVD'
>char filename[EMPTY_ARRAY_SIZE];
>  ^
> ../../include/cdio/iso9660.h:310:20: note: next member 'char 
> iso9660_pvd_s::root_directory_filename' declared here
>char root_directory_filename;  /**< Is '\\0' or root
> ^~~
> In file included from iso9660.cpp:27:0:
> ../../include/cdio++/iso9660.hpp:41:9: note: in the definition of 'class 
> ISO9660::PVD'
>class PVD  // Primary Volume ID
>  ^~~
> Makefile:545: recipe for target 'iso9660.lo' failed
> make[4]: *** [iso9660.lo] Error 1

If the failure looks somehow time/timezone related:
Note that this rebuild was performed without the 'tzdata' package
installed in the chroot. tzdata used be (transitively) part of
build-essential, but it no longer is. If this package requires it to
build, it should be added to build-depends. For the release team's
opinion on this, see
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=836940#185

If the failure looks LSB-related:
similarly to tzdata, lsb-base is not installed in the build chroot.

The full build log is available from:
   http://aws-logs.debian.net/2016/10/21/libcdio_0.83-4.2_unstable.log

A list of current common problems and possible solutions is available at
http://wiki.debian.org/qa.debian.org/FTBFS . You're welcome to contribute!

About the archive rebuild: The rebuild was done on EC2 VM instances from
Amazon Web Services, using a clean, minimal and up-to-date chroot. Every
failed build was retried once to eliminate random failures.