Warning when building SDK on mac

[kevmoo]

tools/build.py -mrelease --arch x64 create_sdk

../../third_party/icu/source/i18n/plurrule.cpp:1576:24: warning: implicit conversion from 'int64_t' (aka 'long long') to 'double' changes value from 9223372036854775807 to 9223372036854775808 [-Wimplicit-int-float-conversion]
          if (scaled > U_INT64_MAX) {
                     ~ ^~~~~~~~~~~
../../third_party/icu/source/common/unicode/umachine.h:223:33: note: expanded from macro 'U_INT64_MAX'
#     define U_INT64_MAX       ((int64_t)(INT64_C(9223372036854775807)))
                                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 warning generated.
[2173/2327] LINK ./gen_snapshot
ld: warning: linker symbol '$ld$hide$os10.4$__Unwind_Backtrace' hides a non-existent symbol '__Unwind_Backtrace'
ld: warning: linker symbol '$ld$hide$os10.5$__Unwind_Backtrace' hides a non-existent symbol '__Unwind_Backtrace'
ld: warning: linker symbol '$ld$hide$os10.4$__Unwind_FindEnclosingFunction' hides a non-existent symbol '__Unwind_FindEnclosingFunction'
ld: warning: linker symbol '$ld$hide$os10.5$__Unwind_FindEnclosingFunction' hides a non-existent symbol '__Unwind_FindEnclosingFunction'
ld: warning: linker symbol '$ld$hide$os10.4$__Unwind_Find_FDE' hides a non-existent symbol '__Unwind_Find_FDE'
ld: warning: linker symbol '$ld$hide$os10.5$__Unwind_Find_FDE' hides a non-existent symbol '__Unwind_Find_FDE'
ld: warning: linker symbol '$ld$hide$os10.4$__Unwind_GetCFA' hides a non-existent symbol '__Unwind_GetCFA'
ld: warning: linker symbol '$ld$hide$os10.5$__Unwind_GetCFA' hides a non-existent symbol '__Unwind_GetCFA'
ld: warning: linker symbol '$ld$hide$os10.4$__Unwind_GetDataRelBase' hides a non-existent symbol '__Unwind_GetDataRelBase'
ld: warning: linker symbol '$ld$hide$os10.5$__Unwind_GetDataRelBase' hides a non-existent symbol '__Unwind_GetDataRelBase'
ld: warning: linker symbol '$ld$hide$os10.4$__Unwind_GetIPInfo' hides a non-existent symbol '__Unwind_GetIPInfo'
ld: warning: linker symbol '$ld$hide$os10.5$__Unwind_GetIPInfo' hides a non-existent symbol '__Unwind_GetIPInfo'
ld: warning: linker symbol '$ld$hide$os10.4$__Unwind_GetTextRelBase' hides a non-existent symbol '__Unwind_GetTextRelBase'
ld: warning: linker symbol '$ld$hide$os10.5$__Unwind_GetTextRelBase' hides a non-existent symbol '__Unwind_GetTextRelBase'
ld: warning: linker symbol '$ld$hide$os10.4$__Unwind_Resume_or_Rethrow' hides a non-existent symbol '__Unwind_Resume_or_Rethrow'
ld: warning: linker symbol '$ld$hide$os10.5$__Unwind_Resume_or_Rethrow' hides a non-existent symbol '__Unwind_Resume_or_Rethrow'
ld: warning: linker symbol '$ld$hide$os10.4$___deregister_frame' hides a non-existent symbol '___deregister_frame'
ld: warning: linker symbol '$ld$hide$os10.5$___deregister_frame' hides a non-existent symbol '___deregister_frame'
ld: warning: linker symbol '$ld$hide$os10.4$___deregister_frame_info' hides a non-existent symbol '___deregister_frame_info'
ld: warning: linker symbol '$ld$hide$os10.5$___deregister_frame_info' hides a non-existent symbol '___deregister_frame_info'
ld: warning: linker symbol '$ld$hide$os10.6$___deregister_frame_info' hides a non-existent symbol '___deregister_frame_info'
ld: warning: linker symbol '$ld$hide$os10.4$___deregister_frame_info_bases' hides a non-existent symbol '___deregister_frame_info_bases'
ld: warning: linker symbol '$ld$hide$os10.5$___deregister_frame_info_bases' hides a non-existent symbol '___deregister_frame_info_bases'
ld: warning: linker symbol '$ld$hide$os10.6$___deregister_frame_info_bases' hides a non-existent symbol '___deregister_frame_info_bases'
ld: warning: linker symbol '$ld$hide$os10.4$___register_frame' hides a non-existent symbol '___register_frame'
ld: warning: linker symbol '$ld$hide$os10.5$___register_frame' hides a non-existent symbol '___register_frame'
ld: warning: linker symbol '$ld$hide$os10.4$___register_frame_info' hides a non-existent symbol '___register_frame_info'
ld: warning: linker symbol '$ld$hide$os10.5$___register_frame_info' hides a non-existent symbol '___register_frame_info'
ld: warning: linker symbol '$ld$hide$os10.6$___register_frame_info' hides a non-existent symbol '___register_frame_info'
ld: warning: linker symbol '$ld$hide$os10.4$___register_frame_info_bases' hides a non-existent symbol '___register_frame_info_bases'
ld: warning: linker symbol '$ld$hide$os10.5$___register_frame_info_bases' hides a non-existent symbol '___register_frame_info_bases'
ld: warning: linker symbol '$ld$hide$os10.6$___register_frame_info_bases' hides a non-existent symbol '___register_frame_info_bases'
ld: warning: linker symbol '$ld$hide$os10.4$___register_frame_info_table' hides a non-existent symbol '___register_frame_info_table'
ld: warning: linker symbol '$ld$hide$os10.5$___register_frame_info_table' hides a non-existent symbol '___register_frame_info_table'
ld: warning: linker symbol '$ld$hide$os10.6$___register_frame_info_table' hides a non-existent symbol '___register_frame_info_table'
ld: warning: linker symbol '$ld$hide$os10.4$___register_frame_info_table_bases' hides a non-existent symbol '___register_frame_info_table_bases'
ld: warning: linker symbol '$ld$hide$os10.5$___register_frame_info_table_bases' hides a non-existent symbol '___register_frame_info_table_bases'
ld: warning: linker symbol '$ld$hide$os10.6$___register_frame_info_table_bases' hides a non-existent symbol '___register_frame_info_table_bases'
ld: warning: linker symbol '$ld$hide$os10.4$___register_frame_table' hides a non-existent symbol '___register_frame_table'
ld: warning: linker symbol '$ld$hide$os10.5$___register_frame_table' hides a non-existent symbol '___register_frame_table'
ld: warning: linker symbol '$ld$hide$os10.6$___register_frame_table' hides a non-existent symbol '___register_frame_table'

[rakudrama]

I get one of the warnings on Linux:

$ tools/build.py -mrelease create_sdk
Syncing projects: 100% (96/96), done.                                                                   
Running hooks: 100% (10/10), done.                
Running hooks: 100% (10/10), done.                
Running python /usr/local/google/home/sra/Dart/sdk/tools/generate_buildfiles.py
ninja -C out/ReleaseX64 create_sdk
ninja: Entering directory `out/ReleaseX64'
[1806/2346] CXX obj/third_party/icu/source/i18n/icui18n.plurrule.o
../../third_party/icu/source/i18n/plurrule.cpp:1576:24: warning: implicit conversion from 'int64_t' (aka 'long') to 'double' changes value from 9223372036854775807 to 9223372036854775808 [-Wimplicit-int-float-conversion]
          if (scaled > U_INT64_MAX) {
                     ~ ^~~~~~~~~~~
../../third_party/icu/source/common/unicode/umachine.h:223:33: note: expanded from macro 'U_INT64_MAX'
#     define U_INT64_MAX       ((int64_t)(INT64_C(9223372036854775807)))
                                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 warning generated.
[2346/2346] STAMP obj/create_sdk.stamp
The build took 150.023 seconds

[dcharkes]

Same on Linux, have been seeing it for some days when building from scratch. Usually in subsequent builds this file has been cached so it doesn't show up anymore.

Since ICU was rolled 10 months ago (4028fec), I don't think it was that. (cc @sstrickl).

Maybe this started when we upgraded clang? (73f6d15) cc @rmacnak-google.

[munificent]

I see this too, every time I build on Mac.

[kevmoo]

@a-siva – thoughts here?

[a-siva]

Yes the warnings are related to the recent upgrade to clang.
The ICU warning requires a roll of ICU not sure who maintains that.

We are still investigating the linker warnings, appears to be harmless but we would like to suppress them.

[a-siva]

@sstrickl you have updated third_party/icu in the past, do you think it would be possible to get a newer version of it that fixes the above warning?

[sstrickl]

I'll take a look later today and see if upgrading it would be a quick fix to the warning issue. I don't recall it being too onerous to update it when I was doing the regex work, but of course can't guarantee that won't be the case for newer versions.

[sstrickl]

So I've checked the chromium ICU repo, and even the latest commit there still has the warning. I'll see about pinging the maintainer of that repo, though, and see if it'd be possible to get a patch that fixes this.

In the meantime, will update our ICU DEPS line to match Flutter's current one, just to make sure we get any changes that have been rolled in since.

[athomas]

Fuchsia also has issues with this warning and disabled it in ICU:
https://fuchsia.googlesource.com/third_party/icu/+/44aba1dafbbe5a9bc9744b4d0373c1b316e30a58%5E%21/#F0

So we could do the same. They also referenced this issue, indicating that the warning might go away when it is resolved: https://unicode-org.atlassian.net/browse/ICU-20869