SERVER-45236 Eliminate need to reiterate compile flags on the link line

2 files changed, 49 insertions, 2 deletions

diff --git a/site_scons/site_tools/mongo_libfuzzer.py b/site_scons/site_tools/mongo_libfuzzer.py
index bcbc0412688..a3718afb0b2 100644
--- a/site_scons/site_tools/mongo_libfuzzer.py
+++ b/site_scons/site_tools/mongo_libfuzzer.py
@@ -44,8 +44,7 @@ def build_cpp_libfuzzer_test(env, target, source, **kwargs):
     libdeps = kwargs.get("LIBDEPS", myenv.get("LIBDEPS", [])).copy()
     kwargs["LIBDEPS"] = libdeps
     kwargs["INSTALL_ALIAS"] = ["tests"]
-    sanitizer_option = "-fsanitize=fuzzer"
-    myenv.Prepend(LINKFLAGS=[sanitizer_option])
+    kwargs["FSAN_DO_LINK"] = True
 
     libfuzzer_test_components = {"tests", "fuzzertests"}
     if "AIB_COMPONENT" in kwargs and not kwargs["AIB_COMPONENTS"].endswith(
diff --git a/site_scons/site_tools/smartlink_cflags.py b/site_scons/site_tools/smartlink_cflags.py
new file mode 100644
index 00000000000..6ebce3d624e
--- /dev/null
+++ b/site_scons/site_tools/smartlink_cflags.py
@@ -0,0 +1,48 @@
+# Copyright 2020 MongoDB Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This tool adjusts the LINKFLAGS and SHLINKFLAGS so that
+# [SH]C[{C,CXX}]FLAGS are reiterated on the link line. This is
+# important for flags like -mmacosx-version-min which has effects at
+# both compile and link time. We use the CXX flags if the sources are
+# C++.
+
+from SCons.Tool.cxx import iscplusplus
+
+def _smartlink_flags(source, target, env, for_signature):
+    if iscplusplus(source):
+        return '$CXXFLAGS $CCFLAGS $CXXLINKFLAGS'
+    return '$CFLAGS $CCFLAGS $CLINKFLAGS'
+
+def _smartshlink_flags(source, target, env, for_signature):
+    if iscplusplus(source):
+        return '$SHCXXFLAGS $SHCCFLAGS $SHCXXLINKFLAGS'
+    return '$SHCFLAGS $SHCCFLAGS $SHCLINKFLAGS'
+
+
+def exists(env):
+    return True
+
+def generate(env):
+
+    if not exists(env):
+        return
+
+    env['SMARTLINKFLAGS'] = _smartlink_flags
+    env['SMARTSHLINKFLAGS'] = _smartshlink_flags
+
+    env.PrependUnique(
+        LINKFLAGS=['$SMARTLINKFLAGS'],
+        SHLINKFLAGS=['$SMARTSHLINKFLAGS'],
+    )