Bug#917980: glib2.0: [experimental] FTBFS on s390x: glib/gvariant-serialiser.c:174:g_variant_serialised_check: assertion failed (alignment & (gsize) serialised.data == 0): (4 == 0)

[Simon McVittie]

Source: glib2.0
Version: 2.58.2-1
Severity: serious
Justification: fails to build from source (but built successfully in the past)

A test fails on s390x. I think this is probably to do with either the
post-2.58.2 patches that I applied, or the GVariant fuzzing fixes in
2.58.2; it might be correlated with s390x being the only 64-bit big-endian
release architecture, or might be a quirk of s390x malloc, or might be
coincidence. (I'm glad I uploaded this to experimental first.)

It's reproducible on zelenka:

#0  0x000003fffda3e66e in raise () from /lib/s390x-linux-gnu/libc.so.6
#1  0x000003fffda23cec in abort () from /lib/s390x-linux-gnu/libc.so.6
#2  0x000003fffde7da46 in g_assertion_message (domain=domain at entry=0x3fffdea47d6 "GLib",
    file=file at entry=0x3fffdf063f6 "../../../glib/gvariant-serialiser.c", line=line at entry=174,
    func=func at entry=0x3fffdf0674c <__FUNCTION__.6010> "g_variant_serialised_check",
    message=message at entry=0x10054f190 "assertion failed (alignment & (gsize) serialised.data == 0): (4 == 0)")
    at ../../../glib/gtestutils.c:2596
#3  0x000003fffde7de20 in g_assertion_message_cmpnum (domain=0x3fffdea47d6 "GLib",
    file=0x3fffdf063f6 "../../../glib/gvariant-serialiser.c", line=<optimized out>,
    func=0x3fffdf0674c <__FUNCTION__.6010> "g_variant_serialised_check", expr=<optimized out>,
    arg1=<optimized out>, cmp=0x3fffdea9954 "==", arg2=<optimized out>, numtype=105 'i')
    at ../../../glib/gtestutils.c:2652
#4  0x000003fffde9ad4e in g_variant_serialised_check (serialised=...) at ../../../glib/gvariant-serialiser.c:174
#5  0x000003fffde9b12c in g_variant_serialised_n_children (serialised=...)
    at ../../../glib/gvariant-serialiser.c:1359
#6  0x000003fffde96090 in g_variant_n_children (value=value at entry=0x1009a32d0) at ../../../glib/gvariant-core.c:950
#7  0x000003fffde916f4 in g_variant_iter_init (iter=iter at entry=0x3ffffffeca0, value=value at entry=0x1009a32d0)
    at ../../../glib/gvariant.c:2976
#8  0x000003fffde92a84 in g_variant_deep_copy (value=value at entry=0x1009a32d0) at ../../../glib/gvariant.c:5797
#9  0x000003fffde95356 in g_variant_get_normal_form (value=0x1009a32d0) at ../../../glib/gvariant.c:5891
#10 0x0000000100008696 in test_normal_checking_tuple_offsets () at ../../../glib/tests/gvariant.c:4941
#11 0x000003fffde7d4ea in test_case_run (tc=0x10002b0d0) at ../../../glib/gtestutils.c:2318
#12 g_test_run_suite_internal (suite=suite at entry=0x100028580, path=path at entry=0x0)
    at ../../../glib/gtestutils.c:2403
#13 0x000003fffde7d370 in g_test_run_suite_internal (suite=suite at entry=0x100028440, path=path at entry=0x0)
    at ../../../glib/gtestutils.c:2415
#14 0x000003fffde7d370 in g_test_run_suite_internal (suite=suite at entry=0x100028420, path=0x0)
    at ../../../glib/gtestutils.c:2415
#15 0x000003fffde7d7aa in g_test_run_suite (suite=0x100028420) at ../../../glib/gtestutils.c:2490
#16 0x000003fffde7d7e0 in g_test_run () at ../../../glib/gtestutils.c:1755
#17 0x0000000100007f5c in main (argc=<optimized out>, argv=<optimized out>) at ../../../glib/tests/gvariant.c:5055

(gdb) p *variant
$1 = {type_info = 0x3fffdf06b30 <g_variant_type_info_basic_table+320>, size = 20, contents = {serialised = {
      bytes = 0x1009a2a90, data = 0x3ffffffee74}, tree = {children = 0x1009a2a90, n_children = 4398046506612}},
  state = 11, ref_count = 1, depth = 0}

    smcv