Use shared gtest instead of submodule

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 617e4b2..2857875 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -18,7 +18,6 @@ set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/cmake/Modules/")
 include(GNUInstallDirs)
 
 project(leelaz)
-add_subdirectory(gtest EXCLUDE_FROM_ALL) # We don't want to install gtest, exclude it from `all`
 
 # Required Packages
 set(Boost_MIN_VERSION "1.58.0")
@@ -27,6 +26,7 @@ find_package(Boost 1.58.0 REQUIRED program_options filesystem)
 find_package(Threads REQUIRED)
 find_package(ZLIB REQUIRED)
 find_package(OpenCL REQUIRED)
+find_package(GTest REQUIRED)
 # We need OpenBLAS for now, because we make some specific
 # calls. Ideally we'd use OpenBLAS is possible and fall back to
 # not doing those calls if it's not present.
@@ -93,6 +93,7 @@ include_directories(${IncludePath})
 include_directories(${Boost_INCLUDE_DIRS})
 include_directories(${OpenCL_INCLUDE_DIRS})
 include_directories(${ZLIB_INCLUDE_DIRS})
+include_directories(${GTEST_INCLUDE_DIRS})
 
 if((UNIX AND NOT APPLE) OR WIN32)
     include_directories(${BLAS_INCLUDE_DIRS})
@@ -141,7 +142,8 @@ target_link_libraries(tests ${Boost_LIBRARIES})
 target_link_libraries(tests ${BLAS_LIBRARIES})
 target_link_libraries(tests ${OpenCL_LIBRARIES})
 target_link_libraries(tests ${ZLIB_LIBRARIES})
-target_link_libraries(tests gtest_main ${CMAKE_THREAD_LIBS_INIT})
+target_link_libraries(tests ${GTEST_BOTH_LIBRARIES})
+target_link_libraries(tests ${CMAKE_THREAD_LIBS_INIT})
 
 include(GetGitRevisionDescription)
 git_describe(VERSION --tags)
='752a5b8fe5c949627b7f68a2780549ba13276403'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=752a5b8fe5c949627b7f68a2780549ba13276403'>root</a>/<a href='/guix/log/tests?id=752a5b8fe5c949627b7f68a2780549ba13276403'>tests</a>/<a href='/guix/log/tests/nar.scm?id=752a5b8fe5c949627b7f68a2780549ba13276403'>nar.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/tests/nar.scm?id=752a5b8fe5c949627b7f68a2780549ba13276403&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2021-11-16 14:34:28 +0100'>2021-11-16</span></td><td><a href='/guix/commit/tests/nar.scm?id=472a0e82a52a3d5d841e1dfad6b13e26082a5750'>daemon: Do not deduplicate files smaller than 8 KiB.</a><span class='msg-avail'>...<span class='msg-tooltip'>Files smaller than 8 KiB typically represent ~70% of the entries in
/gnu/store/.links but only contribute to ~4% of the space savings
afforded by deduplication.

Not considering these files for deduplication speeds up file insertion
in the store and, more importantly, leaves 'removeUnusedLinks' with
fewer entries to traverse, thereby speeding it up proportionally.

Partly fixes &lt;https://issues.guix.gnu.org/24937&gt;.

* config-daemon.ac: Remove symlink hard link check and CAN_LINK_SYMLINK
definition.
* guix/store/deduplication.scm (%deduplication-minimum-size): New
variable.
(deduplicate)[loop]: Do not recurse when FILE's size is below
%DEDUPLICATION-MINIMUM-SIZE.
(dump-port): New procedure.
(dump-file/deduplicate)[hash]: Turn into...
[dump-and-compute-hash]: ... this thunk.
Call 'deduplicate' only when SIZE is greater than
%DEDUPLICATION-MINIMUM-SIZE; otherwise call 'dump-port'.
* nix/libstore/gc.cc (LocalStore::removeUnusedLinks): Drop files where
st.st_size &lt; deduplicationMinSize.
* nix/libstore/local-store.hh (deduplicationMinSize): New declaration.
* nix/libstore/optimise-store.cc (deduplicationMinSize): New variable.
(LocalStore::optimisePath_): Return when PATH is a symlink or smaller
than 'deduplicationMinSize'.
* tests/derivations.scm ("identical files are deduplicated"): Produce
files bigger than %DEDUPLICATION-MINIMUM-SIZE.
* tests/nar.scm ("restore-file-set with directories (signed, valid)"):
Likewise.
* tests/store-deduplication.scm ("deduplicate, below %deduplication-minimum-size"):
New test.
("deduplicate", "deduplicate, ENOSPC"): Produce files bigger than
%DEDUPLICATION-MINIMUM-SIZE.
* tests/store.scm ("substitute, deduplication"): Likewise.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-12-15 17:32:09 +0100'>2020-12-15</span></td><td><a href='/guix/commit/tests/nar.scm?id=2718c29c3fb9f9de2ec897248ad49ae11ca39b7a'>nar: Deduplicate files right as they are restored.</a><span class='msg-avail'>...<span class='msg-tooltip'>This avoids having to traverse and re-read the files that we have just
restored, thereby reducing I/O.

* guix/serialization.scm (dump-file): New procedure.
(restore-file): Add #:dump-file parameter and honor it.
* guix/store/deduplication.scm (tee, dump-file/deduplicate): New
procedures.
* guix/nar.scm (restore-one-item): Pass #:dump-file to 'restore-file'.
(finalize-store-file): Pass #:deduplicate? #f to 'register-items'.
* tests/nar.scm &lt;top level&gt;: Call 'setenv' to set "NIX_STORE".
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-12-15 17:32:09 +0100'>2020-12-15</span></td><td><a href='/guix/commit/tests/nar.scm?id=ed7d02f7c198970ce3fe94bcee47592963326446'>serialization: 'restore-file' sets canonical timestamp and permissions.</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/serialization.scm (restore-file): Set the permissions and mtime
of FILE.
* guix/nar.scm (finalize-store-file): Pass #:reset-timestamps? #f to
'register-items'.
* tests/nar.scm (rm-rf): Add 'chmod' calls to ensure files are writable.
("write-file + restore-file with symlinks"): Ensure every file in OUTPUT
passes 'canonical-file?'.
* tests/guix-archive.sh: Run "chmod -R +w" before "rm -rf".
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-12-15 17:32:09 +0100'>2020-12-15</span></td><td><a href='/guix/commit/tests/nar.scm?id=465d2cb286170933577de045e6e6dad7205bfe10'>serialization: 'fold-archive' notifies about directory processing completion.</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/serialization.scm (fold-archive): Call PROC with a
'directory-complete tag when done with a directory.
(restore-file): Handle it.
* guix/scripts/archive.scm (list-contents): Likewise.
* guix/scripts/challenge.scm (archive-contents): Likewise.
* tests/nar.scm ("write-file-tree + fold-archive"): Adjust accordingly.
</span></span></td><td>Ludovic Courtès</td></tr>