Stop forcing -Wl,--as-needed on dependents

Commit 8081530e824c092d36b1ef7947783c5859eb8b61 added -Wl,--as-needed
-latomic -Wl,--no-as-needed to ensure libatomic got linked on platforms
that needed it (see https://bugs.debian.org/973492). However, this
inadventantly added -Wl,--no-as-needed to dependents’ link lines when
they built with CMake. Switch to -Wl,--push-state,--as-needed -latomic
-Wl,--pop-state instead to ensure dependents’ link settings remain
intact. As an added bonus, this removes -Wl,--as-needed from the Abseil
build itself, allowing a bunch of libraries that don’t actually need
libc to omit a libc dependency.

Closes: https://bugs.debian.org/1001596

3 files changed, 24 insertions, 1 deletions

diff --git a/debian/changelog b/debian/changelog
index f69c9522..0347674f 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -4,6 +4,7 @@ abseil (0~20210324.2-1) UNRELEASED; urgency=medium
   * Correct debian/watch search URLs to avoid picking up rc versions.
   * Mangle upstream version in debian/watch to match manual mangling in
     debian/changelog.
+  * Stop forcing -Wl,--no-as-needed on dependents. (Closes: #1001596)
   * Compute Thumb function bounds correctly. (Closes: #987314)
   * Reenable unit tests on arm64 and mips64el.
 
diff --git a/debian/libabsl20210324.lintian-overrides b/debian/libabsl20210324.lintian-overrides
index 7557abac..eda83e40 100644
--- a/debian/libabsl20210324.lintian-overrides
+++ b/debian/libabsl20210324.lintian-overrides
@@ -12,5 +12,27 @@
 # License for the specific language governing permissions and limitations under
 # the License.
 
+libabsl20210324: library-not-linked-against-libc usr/lib/*/libabsl_bad_any_cast_impl.so*
+libabsl20210324: library-not-linked-against-libc usr/lib/*/libabsl_bad_optional_access.so*
+libabsl20210324: library-not-linked-against-libc usr/lib/*/libabsl_bad_variant_access.so*
+libabsl20210324: library-not-linked-against-libc usr/lib/*/libabsl_exponential_biased.so*
+libabsl20210324: library-not-linked-against-libc usr/lib/*/libabsl_flags_commandlineflag.so*
+libabsl20210324: library-not-linked-against-libc usr/lib/*/libabsl_flags_commandlineflag_internal.so*
+libabsl20210324: library-not-linked-against-libc usr/lib/*/libabsl_hash.so*
+libabsl20210324: library-not-linked-against-libc usr/lib/*/libabsl_hashtablez_sampler.so*
+libabsl20210324: library-not-linked-against-libc usr/lib/*/libabsl_log_severity.so*
+libabsl20210324: library-not-linked-against-libc usr/lib/*/libabsl_periodic_sampler.so*
+libabsl20210324: library-not-linked-against-libc usr/lib/*/libabsl_random_internal_randen.so*
+libabsl20210324: library-not-linked-against-libc usr/lib/*/libabsl_random_internal_randen_hwaes_impl.so*
+libabsl20210324: library-not-linked-against-libc usr/lib/*/libabsl_random_internal_randen_slow.so*
+libabsl20210324: library-not-linked-against-libc usr/lib/*/libabsl_stacktrace.so*
+libabsl20210324: library-not-linked-against-libc usr/lib/*/libabsl_throw_delegate.so*
 libabsl20210324: no-symbols-control-file usr/lib/*/libabsl_*
 libabsl20210324: package-name-doesnt-match-sonames libabsl-*
+libabsl20210324: shared-library-lacks-prerequisites usr/lib/*/libabsl_city.so*
+libabsl20210324: shared-library-lacks-prerequisites usr/lib/*/libabsl_flags.so*
+libabsl20210324: shared-library-lacks-prerequisites usr/lib/*/libabsl_leak_check.so*
+libabsl20210324: shared-library-lacks-prerequisites usr/lib/*/libabsl_leak_check_disable.so*
+libabsl20210324: shared-library-lacks-prerequisites usr/lib/*/libabsl_random_internal_platform.so*
+libabsl20210324: shared-library-lacks-prerequisites usr/lib/*/libabsl_random_internal_randen_hwaes.so*
+libabsl20210324: shared-library-lacks-prerequisites usr/lib/*/libabsl_wyhash.so*
diff --git a/debian/patches/latomic.diff b/debian/patches/latomic.diff
index 404144e2..861f20bf 100644
--- a/debian/patches/latomic.diff
+++ b/debian/patches/latomic.diff
@@ -14,7 +14,7 @@ if anything needs libatomic and add the DT_NEEDED entry where necessary.
  endif()
  
 +list(APPEND ABSL_DEFAULT_LINKOPTS
-+    "-Wl,--as-needed" "-latomic" "-Wl,--no-as-needed"
++    "-Wl,--push-state,--as-needed" "-latomic" "-Wl,--pop-state"
 +)
 +
  set(ABSL_CXX_STANDARD "${CMAKE_CXX_STANDARD}")