754171 - Failed to build at config/elf-dynstr-gc.c and nsTraceMalloc.c

Status: RESOLVED FIXED

(Firefox Build System :: General, defect)

Description

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

When I build a debug build on Ubuntu 11.10 (x86), I got following error:

> config/elf-dynstr-gc.c:1237:12: エラー: warn_unused_result 属性付きで宣言されている ‘ftruncate’ の戻り値を無視しています [-Werror=unused-result]

It said, result value of "ftruncate" is ignored but it's defined with "warn_unused_result".

If I add "--enable-trace-malloc" to my .mozconfig, the file is never compiled, but I can see same error at nsTraceMalloc.c.

> /tools/trace-malloc/lib/nsTraceMalloc.c:1352:5: エラー: warn_unused_result 属性付きで宣言されている ‘write’ の戻り値を無視しています [-Werror=unused-result]
> /tools/trace-malloc/lib/nsTraceMalloc.c:1353:5: エラー: warn_unused_result 属性付きで宣言されている ‘write’ の戻り値を無視しています [-Werror=unused-result]

I guess that bug 736501 could cause this bug because the file hasn't been changed and I couldn't see this build error last month.

my .mozconfig file is:

ac_add_options --enable-debug
ac_add_options --enable-tests
ac_add_options --enable-logging
ac_add_options --disable-installer
ac_add_options --disable-crashreporter

Comment 1

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

My gcc version is 4.6.1-9ubuntu3.

Comment 2

[Aryeh Gregor (:ayg) (no longer with Mozilla)]

Me too.  I tried fixing that specific call, but then I got more errors:

/mnt/extra/checkouts/mozilla-central/memory/jemalloc/jemalloc.c:1530:7: error: ignoring return value of ‘write’, declared with attribute warn_unused_result [-Werror=unused-result]
/mnt/extra/checkouts/mozilla-central/memory/jemalloc/jemalloc.c:1531:7: error: ignoring return value of ‘write’, declared with attribute warn_unused_result [-Werror=unused-result]
/mnt/extra/checkouts/mozilla-central/memory/jemalloc/jemalloc.c:1532:7: error: ignoring return value of ‘write’, declared with attribute warn_unused_result [-Werror=unused-result]
/mnt/extra/checkouts/mozilla-central/memory/jemalloc/jemalloc.c:1533:7: error: ignoring return value of ‘write’, declared with attribute warn_unused_result [-Werror=unused-result]

I think this needs to be backed out, or made conditional somehow.  Given that this is like the second time in a week that a checkin broke the build on Ubuntu, it would be really nice if we could invest in some Ubuntu tinderboxen for at least compile-testing, even if we don't run all tests on them . . .

Comment 3

[Aryeh Gregor (:ayg) (no longer with Mozilla)]

Backing out the commit (hg backout 6a7bfd84596e) results in a successful compile.

Comment 4

[Benjamin Smedberg]

The patch in bug 754198 covers this bustage as well, although it tried to wallpaper over an actual error, so I'm opposed to backing the error out.

Comment 5

[[:fabrice] Fabrice Desré]

fixed in bug 754198