Found that the curl failed to build on FreeBSD with errors:
gmake[2]: Entering directory '/home/vagrant/tarantool/third_party/curl/src'
  CCLD     curl
/usr/local/bin/ld: ../lib/.libs/libcurl.so: undefined reference to `SSLv23_client_method'
/usr/local/bin/ld: ../lib/.libs/libcurl.so: undefined reference to `CONF_modules_free'
/usr/local/bin/ld: ../lib/.libs/libcurl.so: undefined reference to `ERR_free_strings'
/usr/local/bin/ld: ../lib/.libs/libcurl.so: undefined reference to `sk_value'
/usr/local/bin/ld: ../lib/.libs/libcurl.so: undefined reference to `ENGINE_cleanup'
/usr/local/bin/ld: ../lib/.libs/libcurl.so: undefined reference to `SSL_library_init'
/usr/local/bin/ld: ../lib/.libs/libcurl.so: undefined reference to `EVP_MD_CTX_destroy'
/usr/local/bin/ld: ../lib/.libs/libcurl.so: undefined reference to `sk_pop_free'
/usr/local/bin/ld: ../lib/.libs/libcurl.so: undefined reference to `SSLeay'
/usr/local/bin/ld: ../lib/.libs/libcurl.so: undefined reference to `SSL_get_ex_new_index'
/usr/local/bin/ld: ../lib/.libs/libcurl.so: undefined reference to `OPENSSL_add_all_algorithms_noconf'
/usr/local/bin/ld: ../lib/.libs/libcurl.so: undefined reference to `SSL_COMP_free_compression_methods'
/usr/local/bin/ld: ../lib/.libs/libcurl.so: undefined reference to `EVP_MD_CTX_create'
/usr/local/bin/ld: ../lib/.libs/libcurl.so: undefined reference to `EVP_cleanup'
/usr/local/bin/ld: ../lib/.libs/libcurl.so: undefined reference to `sk_num'
/usr/local/bin/ld: ../lib/.libs/libcurl.so: undefined reference to `sk_pop'
/usr/local/bin/ld: ../lib/.libs/libcurl.so: undefined reference to `SSL_load_error_strings'
collect2: error: ld returned 1 exit status
gmake[2]: *** [Makefile:921: curl] Error 1

Found root cause of the issue at the `./configure <...>` output:
 | checking for OpenSSL headers version... 1.0.2 - 0x1000214fL
 | checking for OpenSSL library version... 1.1.1
 | configure: WARNING: OpenSSL headers and library versions do not match.
It is seen that the Tarantool bootstrap installed pkg 'openssl'
of the version '1.0.2', while the currently default FreeBSD 'openssl'
version was '1.1.1'.

Anyway we don't need any special openssl version installed against
default one, so the fix is just to remove the openssl package from
bootstrap installation.
Also found that some installing packages are not needed too,
removed it from FreeBSD bootstrap.

Additionally added libiconv library into bootstrap which is needed
as workaround to avoid of the issue described in:
	https://github.com/tarantool/tarantool/issues/3791

Closed #4490

(cherry picked from commit 1f2338bd)

`apt-get update <...>` fails on Debian Buster on docker_bootstrap goal
(see #4331 for the similar issue).

Added a description how to change dependencies in .travis.mk.

(cherry picked from commit 45c2576d)

Hold libcurl-7.65.3. This version is not affected by the following
issues:

* #4180 ('httpc: redirects are broken with libcurl-7.30 and older');
* #4389 ('libcurl memory leak');
* #4397 ('HTTPS seem to be unstable').

After this patch libcurl will be statically linked when
ENABLE_BUNDLED_LIBCURL option is set. This option is set by default.

Closes #4318

@TarantoolBot document
Title: Tarantool dependency list was changed

* Added build dependencies: autoconf, automake, libtool, zlib-devel
  (zlib1g-dev on Debian).
* Added runtime dependencies: zlib (zlib1g on Debian).
* Removed build dependencies: libcurl-devel (libcurl4-openssl-dev on
  Debian).
* Removed runtime dependencies: curl.

The reason is that now we use compiled-in libcurl: so we don't depend on
a system libcurl, but inherit its dependencies.

(cherry picked from commit 7e51aebb)

Increased the maximum number of open file descriptors on macOS.

Travis-ci: needed the "ulimit -n <value>" call, because found
that the tests fail without it even with launchctl limit tool set.

Gitlab-ci: needed the "launchctl limit maxfiles <value>" call,
because under gitlib-ci it is needed the password to change the
limits and we call the sudo tool which separates the local set
of the environment.

Closes #4373

Due to the new 7.65.3 curl version released on 2019-07-19,
removed temporary workaround that downgraded the curl to
7.65.0.

This reverts commit 2e880af0.

Follows up #4288

Enabled complete testing for OSX, temporary skipped the
failed suite replication/ and tests engine/replica_join
with issue #4370 and small/quota from repository
https://github.com/tarantool/small.git with issue #4357
to enable it back. Also fixed the OSX ulimit setup
different for VBOX and Travis-ci images.

Closes #4358

Added ASAN tesing in commit process, used clang-8 for
ASAN build under debian-buster image. Added for testing
only the passing test suites, the rest of the tests
not used and will be enabled durring issue #4360. Also
fixed job for testing LTO with clang on debian-buster
in travis-ci, changed it to the same as in gitlab-ci,
changed default clang to clang-8.

Closes #4359

travis-ci APT repository update failed on Debian 10 (Buster)
with command 'apt-get update', like:

Get:1 http://deb.debian.org/debian buster InRelease [118 kB]
Get:2 http://security.debian.org/debian-security buster/updates InRelease [39.1 kB]
Get:3 http://deb.debian.org/debian buster-updates InRelease [46.8 kB]
Reading package lists... Done
N: Repository 'http://security.debian.org/debian-security buster/updates InRelease' changed its 'Version' value from '' to '10'
E: Repository 'http://security.debian.org/debian-security buster/updates InRelease' changed its 'Suite' value from 'testing' to 'stable'
N: This must be accepted explicitly before updates for this repository can be applied. See apt-secure(8) manpage for details.
N: Repository 'http://deb.debian.org/debian buster InRelease' changed its 'Version' value from '' to '10.0'
E: Repository 'http://deb.debian.org/debian buster InRelease' changed its 'Suite' value from 'testing' to 'stable'
N: This must be accepted explicitly before updates for this repository can be applied. See apt-secure(8) manpage for details.
E: Repository 'http://deb.debian.org/debian buster-updates InRelease' changed its 'Suite' value from 'testing-updates' to 'stable-updates'
N: This must be accepted explicitly before updates for this repository can be applied. See apt-secure(8) manpage for details.

The cause of the issue was:

According to Debian Project News published 1st of July, Debian 10 "Buster"
was scheduled to transition from testing to stable on 2019-07-06.
It looks like the transition was in fact performed as scheduled, and so the
testing distribution should now be catching up witn unstable, to eventually
become Debian 11 "Bullseye". You might be experiencing some temporary side
effects because of this transition of the Debian mirrors.
If you want to stay with Debian 10 "Buster", now would be a good time to switch
your /etc/apt/sources.list to use the release name buster instead of testing.
Otherwise, you'll soon be getting the raw bleeding-edge stuff from unstable,
and you might accidentally get a partial upgrade to proto-"Bullseye".
Also, this is a reminder for anyone using the word stable in their
/etc/apt/sources.list to consider whether to change it to stretch and stay with
the old version, or read the Release Notes and perform the recommended upgrade
steps.

To fix the issue it had to accept interactively the changes in the repositories
NOTE: apt instead of apt-get can accept the changes interactively

apt update -y

either accept only the needed changes for 'version' and 'suite'

apt-get update --allow-releaseinfo-change-version --allow-releaseinfo-change-suite

Seems that the only 'version' and 'suite' accept is better than blind
accept of the all changes.

Closes #4331

Homebrew now contains curl-7.65.1 which affected by curl/curl#3995 (this
problem leads to segfaults). The next version is not released yet. The
current commit downgrades the curl version to 7.65.0.

Close #4288

Implemented GitLab CI testing process additionally to existing Travis
CI. The new testing process is added to run tests faster. It requires to
control a load of machines to avoid flaky fails on timeouts. GitLab CI
allows us to run testing on our machines.

Created 2 stages for testing and deploying packages.

The testing stage contains the following jobs that are run for all
branches:

* Debian 9 (Stretch): release/debug gcc.
* Debian 10 (Buster): release clang8 + lto.
* OSX 14 (Mojave): release.
* FreeBSD 12: release gcc.

And the following jobs that are run of long-term branches (release
branches: for now it is 1.10, 2.1 and master):

* OSX 13 (Sierra): release clang.
* OSX 14 (Mojave): release clang + lto.

The deployment stage contains the same jobs as we have in Travis CI.
They however just build tarballs and packages: don't push them to S3 and
packagecloud.

In order to run full testing on a short-term branch one can name it with
'-full-ci' suffix.

The additional manual work is needed when dependencies are changed in
.travis.mk file ('deps_debian' or 'deps_buster_clang_8' goals):

 | make GITLAB_USER=foo -f .gitlab.mk docker_bootstrap

This command pushes docker images into GitLab Registry and then they are
used in testing. Pre-built images speed up testing.

Fixes #4156

Travis-ci failed on brew install python2 due to it was
already installed on OSX 10.13 Sierra, so it needs
to be installed without fails on its exists.

Follow up #4254

Removed skip flag file to switch on the testing of the
http_client test. Enabled http_client test on OSX,
fixed missing of the python2 symlink. Removed the subtest
on '595 error return' from 'error' suite, due to it may
hang forever. To enable test on travis-ci reverted commit:

1d7285c4 ('Disable flaky http_client.test.lua')

Closes #4254

Made fixes:

- Added CMAKE_EXTRA_PARAMS environment to docker's container
  runs to enable -DENABLE_LTO=ON/OFF cmake option.

- Added CC/CXX environment to docker's container runs to set
  clang for cmake. Also the additional environment variables
  {CC,CXX}_FOR_BUILD were postponed, because we didn't
  run cross-compilation at the moment, for more info check:

    https://docs.travis-ci.com/user/languages/cpp/#choosing-compilers-to-test-against

- Changed LTO docker's image to 'debian-buster' due to LTO needed
  higher versions of packages, check for more information commit:

    f9e28ce4 ('Add LTO support')

- Fixed sources to avoid of failures on builds by GCC with LTO:

1)  src/box/memtx_rtree.c: In function ‘mp_decode_rect’:
    src/box/memtx_rtree.c:86:24: error: ‘c’ may be used uninitialized
      in this function [-Werror=maybe-uninitialized]
        rect->coords[i * 2] = c;
                            ^
    src/box/memtx_rtree.c:74:10: note: ‘c’ was declared here
      coord_t c;
              ^

2)  src/box/sql/func.c: In function ‘quoteFunc’:
    src/box/sql/func.c:1103:3: error: ‘b’ may be used uninitialized
      in this function [-Werror=maybe-uninitialized]
       sql_result_text(context, sql_value_boolean(argv[0]) ?
       ^
    src/box/sql/vdbeapi.c:217:7: note: ‘b’ was declared here
      bool b;
           ^

3)  src/box/tuple_update.c: In function ‘update_read_ops’:
    src/box/tuple_update.c:1022:4: error: ‘field_no’ may be used
      uninitialized in this function [-Werror=maybe-uninitialized]
        diag_set(ClientError, ER_NO_SUCH_FIELD_NO, field_no);
        ^
    src/box/tuple_update.c:1014:11: note: ‘field_no’ was declared here
       int32_t field_no;
               ^

4)  src/httpc.c: In function ‘httpc_set_verbose’:
    src/httpc.c:267:2: error: call to ‘_curl_easy_setopt_err_long’
      declared with attribute warning: curl_easy_setopt expects a long
      argument for this option [-Werror]
      curl_easy_setopt(req->curl_request.easy, CURLOPT_VERBOSE, curl_verbose);
      ^

5)  src/lua/httpc.c: In function ‘luaT_httpc_request’:
    src/lua/httpc.c:128:64: error: ‘MEM[(int *)&parser + 20B]’ may be used
      uninitialized in this function [-Werror=maybe-uninitialized]
      lua_pushinteger(L, (parser.http_minor > 0) ? parser.http_minor: 0);
                                                                    ^
    src/lua/httpc.c:67:21: note: ‘MEM[(int *)&parser + 20B]’ was declared here
      struct http_parser parser;
                         ^
    src/lua/httpc.c:124:64: error: ‘MEM[(int *)&parser + 16B]’ may be used
      uninitialized in this function [-Werror=maybe-uninitialized]
      lua_pushinteger(L, (parser.http_major > 0) ? parser.http_major: 0);
                                                                    ^
    src/lua/httpc.c:67:21: note: ‘MEM[(int *)&parser + 16B]’ was declared here
      struct http_parser parser;
                         ^

Close #4215

Added --force flag to travis-ci jobs not to stop on failed tests.
Due to any found failed test breaks the testing it masks the other
fails and in the following ways it's not good:
- flaky test masks real problem
- release testing needs overall result to fix it fast
- parallel testing may produce flaky test

Close: #4131

It is important to have testing jobs that build the project with both
-Werror and -O2 to keep the code clean. -O2 is needed, because some
compiler warnings are available only after extra analyzing passes that
are disabled with lesser optimization levels.

The first attempt to add -Werror for release testing jobs was made in
da505ee7 ('Add -Werror for CI (1.10
part)'), but it mistakely doesn't enable -O2 for RelWithDebInfoWError
build. It is possible to fix it in this way:

 | --- a/cmake/compiler.cmake
 | +++ b/cmake/compiler.cmake
 | @@ -113,10 +113,14 @@ set (CMAKE_C_FLAGS_DEBUG
 |      "${CMAKE_C_FLAGS_DEBUG} ${CC_DEBUG_OPT} -O0")
 |  set (CMAKE_C_FLAGS_RELWITHDEBINFO
 |      "${CMAKE_C_FLAGS_RELWITHDEBINFO} ${CC_DEBUG_OPT} -O2")
 | +set (CMAKE_C_FLAGS_RELWITHDEBINFOWERROR
 | +    "${CMAKE_C_FLAGS_RELWITHDEBINFOWERROR} ${CC_DEBUG_OPT} -O2")
 |  set (CMAKE_CXX_FLAGS_DEBUG
 |      "${CMAKE_CXX_FLAGS_DEBUG} ${CC_DEBUG_OPT} -O0")
 |  set (CMAKE_CXX_FLAGS_RELWITHDEBINFO
 |      "${CMAKE_CXX_FLAGS_RELWITHDEBINFO} ${CC_DEBUG_OPT} -O2")
 | +set (CMAKE_CXX_FLAGS_RELWITHDEBINFOWERROR
 | +    "${CMAKE_CXX_FLAGS_RELWITHDEBINFOWERROR} ${CC_DEBUG_OPT} -O2")
 |
 |  unset(CC_DEBUG_OPT)

However I think that a build type (and so `tarantool --version`) should
not show whether -Werror was passed or not. So I have added
ENABLE_WERROR CMake option for that. It can be set like so:

 | cmake . -DCMAKE_BUILD_TYPE=RelWithDebInfo -DENABLE_WERROR=ON

Enabled the option in testing Travis-CI jobs with the RelWithDebInfo
build type. Deploy jobs don't include it as before.

Fixed all -Wmaybe-uninitialized and -Wunused-result warnings. A few
notes about the fixes:

* net.box does not validate received data in general, so I don't add a
  check for autoincrement IDs too. Set the ID to INT64_MIN, because this
  value is less probably will appear here in a normal case and so is the
  best one to signal a user that something probably going wrongly.
* xrow_decode_*() functions could read uninitialized data from
  row->body[0].iov_base in xrow_on_decode_err() when printing a hex code
  for a row. It could be possible when the received msgpack was empty
  (row->bodycnt == 0), but there were expected keys (key_map != 0).
* getcwd() is marked with __attribute__((__warn_unused_result__)) in
  glibc, but the buffer filled by this call is not used anywhere and so
  just removed.
* Vinyl -Wmaybe-uninitialized warnings are false positive ones.

Added comments and quotes into .travis.yml to ease reading. Removed
"test" word from the CentOS 6 job name, because we don't run tests on
this distro (disabled in the RPM spec).

Fixes #4178.

Fixed Mojave Mac build with setting MACOSX_DEPLOYMENT_TARGET environment
variable for LuaJIT's Makefile. This variable specifies the minimum
version of OS X on which the target binaries are to be deployed.

The reason why we need to set MACOSX_DEPLOYMENT_TARGET to at least 10.6
is that 10.4 SDK (which is set by default in LuaJIT's Makefile) is not
longer included in Mac OS X Mojave 10.14.

See also https://github.com/LuaJIT/LuaJIT/issues/484

We already set -Wl,-macosx_version_min,10.6 (-macosx_version_min and
MACOSX_DEPLOYMENT_TARGET are synonymous), but it affects only a linker.
We possibly should remove -macosx_version_min, because it superseded by
MACOSX_DEPLOYMENT_TARGET, but it should be done with verification that
the original problem really fixed by the new way to set a deployment
target. This is not part of this patch.

Removed virtualenv usage in CI for OS X (so pip just installs packages
into a system), because OS X Mojave 10.14 does not offer virtualenv by
default.

Fixed #3797

Upload tarballs of alpha and beta tarantool versions (*.0 and *.1
branches) into 2x (3x, 4x...) buckets. See more details about the
release process in the documentation: [1].

[1]: https://tarantool.io/en/doc/2.0/dev_guide/release_management/

Added MAKE_BUILD_TYPE=RelWithDebInfoWError option, which means enabling
-DNDEBUG=1, -O2 and -Wall -Wextra -Werror. This ensures we have clean
release build without warnings.

Fixed found -Wunused-variable and -Wunused-parameter warnings.

Part of #3238.

The -j -1 used to legacy consistent mode. Reducing the number of jobs
to one by switching to -j 1, uses same part of the code as in parallel
mode. The code in parallel mode kills hung tests.

Part of https://github.com/tarantool/test-run/issues/106

The reason of the failures is TLSv1.0/TLSv1.1 brownout on the PyPI side,
see [1] for more information.

[1]: pypa/packaging-problems#130

Rewrote TCL scripts as posix shell ones, enabled SQL_MAINTAINER_MODE
commands unconditionally.

Rewrote cmake targets to generate those files in a build directory
instead of the source directory.

Fixes #3183.

The reason of the failures is TLSv1.0/TLSv1.1 brownout on the PyPI side,
see [1] for more information.

[1]: pypa/packaging-problems#130

* Added new coveralls options to sync repo

* Pass travis job to coverage docker

* Added new coveralls options to sync repo

* Pass travis job to coverage docker

Try to fix coverage.

Switched from ubuntu zesty to artful, since zesty is EOLed on 13Jan2018

Travis images are broken by design.

Ubuntu Trusty on Travis is buggy.

Fixes #2752

Ubuntu Trusty on Travis is buggy.

Fixes #2752

Inpspired by tarantool/curl module by Vasiliy Soshnikov.
Reviewed and refactored by Roman Tsisyk.

Closes #2083