build: add option for reducing exports

Enabled automatically if boost >= 1.49.
See: https://svn.boost.org/trac/boost/ticket/2309

Also, check for a default visibility attribute, so that we can mark future
api functions correctly.

src/Makefile.am

@@ -262,6 +262,7 @@ endif
 
 bitcoind_LDADD += $(BOOST_LIBS) $(BDB_LIBS) $(SSL_LIBS) $(CRYPTO_LIBS)
 bitcoind_CPPFLAGS = $(BITCOIN_INCLUDES)
+bitcoind_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS)
 
 # bitcoin-cli binary #
 bitcoin_cli_LDADD = \
@@ -299,10 +300,12 @@ endif
 bitcoin_tx_SOURCES = bitcoin-tx.cpp
 bitcoin_tx_CPPFLAGS = $(BITCOIN_INCLUDES)
 #
+bitcoin_tx_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS)
 
 if TARGET_WINDOWS
 bitcoin_cli_SOURCES += bitcoin-cli-res.rc
 endif
+bitcoin_cli_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS)
 
 CLEANFILES = leveldb/libleveldb.a leveldb/libmemenv.a *.gcda *.gcno
 

src/Makefile.qt.include

@@ -362,7 +362,7 @@ qt_bitcoin_qt_LDADD += $(LIBBITCOIN_CLI) $(LIBBITCOIN_COMMON) $(LIBBITCOIN_UTIL)
 if USE_LIBSECP256K1
   qt_bitcoin_qt_LDADD += secp256k1/libsecp256k1.la
 endif
-qt_bitcoin_qt_LDFLAGS = $(AM_LDFLAGS) $(QT_LDFLAGS)
+qt_bitcoin_qt_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(QT_LDFLAGS)
 
 #locale/foo.ts -> locale/foo.qm
 QT_QM=$(QT_TS:.ts=.qm)

src/Makefile.qttest.include

@@ -36,7 +36,7 @@ qt_test_test_bitcoin_qt_LDADD += $(LIBBITCOIN_CLI) $(LIBBITCOIN_COMMON) $(LIBBIT
 if USE_LIBSECP256K1
   qt_test_test_bitcoin_qt_LDADD += secp256k1/libsecp256k1.la
 endif
-qt_test_test_bitcoin_qt_LDFLAGS = $(AM_LDFLAGS) $(QT_LDFLAGS)
+qt_test_test_bitcoin_qt_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(QT_LDFLAGS)
 
 CLEAN_BITCOIN_QT_TEST = $(TEST_QT_MOC_CPP) qt/test/*.gcda qt/test/*.gcno
 

src/Makefile.test.include

@@ -75,6 +75,7 @@ if USE_LIBSECP256K1
 endif
 
 test_test_bitcoin_LDADD += $(BDB_LIBS) $(SSL_LIBS) $(CRYPTO_LIBS)
+test_test_bitcoin_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS)
 
 nodist_test_test_bitcoin_SOURCES = $(GENERATED_TEST_FILES)