mono · jaykrell · Jul 29, 2018 · Jul 25, 2018 · Jul 25, 2018 · Jul 25, 2018
diff --git a/configure.ac b/configure.ac
@@ -691,7 +691,8 @@ AC_ARG_ENABLE(visibility-hidden,
 
 WARN=''
 if test x"$GCC" = xyes; then
-        WARN='-Wall -Wunused -Wmissing-prototypes -Wmissing-declarations -Wstrict-prototypes  -Wmissing-prototypes -Wnested-externs -Wpointer-arith -Wno-cast-qual -Wwrite-strings -Wno-switch -Wno-switch-enum -Wno-unused-value -Wno-attributes -Wno-format-zero-length'
+		WARN='-Wall -Wunused -Wmissing-declarations -Wpointer-arith -Wno-cast-qual -Wwrite-strings -Wno-switch -Wno-switch-enum -Wno-unused-value -Wno-attributes'
+		CFLAGS="$CFLAGS -Wmissing-prototypes -Wstrict-prototypes -Wnested-externs -Wno-format-zero-length"
 
 		# We require C99 with some GNU extensions, e.g. `linux` macro
 		CFLAGS="$CFLAGS -std=gnu99"
@@ -978,7 +979,6 @@ AC_SUBST(JEMALLOC_LDFLAGS)
 AC_SUBST(JEMALLOC_AUTOCONF_FLAGS)
 fi
 
-
 # Terminology:
 # Crash privacy - Attempts to not send identifying information in the crash dump / to protect the obscurity of the program control flow
 # MERP - The MS telemetry profile. Not for general use.
@@ -1016,6 +1016,43 @@ if test x$enable_monotouch = xyes; then
 	AC_DEFINE(ENABLE_MONOTOUCH, 1, [Enable runtime support for Monotouch (Xamarin.iOS and Xamarin.Mac)])
 fi
 
+AC_ARG_ENABLE(cxx, [  --enable-cxx   compile some code as C++])
+
+if test "x$enable_cxx" = "xyes"; then
+
+	# FIXME Centos6 requires a different flag for prerelease C++11.
+	#CXX_ADD_CFLAGS=' -xc++ -std=gnu++98 -fno-exceptions -fno-rtti '
+	CXX_ADD_CFLAGS=' -xc++ -std=gnu++11 -fno-exceptions -fno-rtti '
+
+	# -std=gnu99 -xc++ is not allowed and errors.
+	CXX_REMOVE_CFLAGS=-std=gnu99
+	# These give warnings and should be removed. They are C-only.
+	# i.e. C++ never allows these, they are always errors and their warningness is not controllable.
+	CXX_REMOVE_CFLAGS="$CXX_REMOVE_CFLAGS -Wmissing-prototypes -Wstrict-prototypes -Wnested-externs"
+	# Likewise with CentOS 6 gcc 4.4.
+	CXX_REMOVE_CFLAGS="$CXX_REMOVE_CFLAGS -Werror-implicit-function-declaration"
+
+	# The C-only-ness of -Wno-format-zero-length varies with gcc version.
+	# It is C-only prior to 4.7. Using it with C++ prior to 4.7
+	# generates a warning every time we run gcc which is very unsightly.
+	# The warning is for e.g. sprintf(foo, "") which can just be
+	# foo[0] = 0 but Mono's use is more elaborate, not as easy to "fix",
+	# and completely legal and valid.
+	# We have to switch to C++ and not just use -xc++ because of -std=gnu99 (error when combined with -xc++).
+	# Alternatively, just run $CXX -xc++ -c /dev/null.
+	AC_LANG_PUSH(C++)
+	ORIG_CXXFLAGS=$CXXFLAGS
+	CXXFLAGS="$CXXFLAGS -Werror -Wno-format-zero-length -xc++ "
+	AC_MSG_CHECKING(or C-only-ness of -Wno-format-zero-length)
+	AC_TRY_COMPILE([ ], [ ], [ AC_MSG_RESULT(yes) ],
+				 [ AC_MSG_RESULT(no)
+				   CXX_REMOVE_CFLAGS="$CXX_REMOVE_CFLAGS -Wno-format-zero-length" ])
+	CXXFLAGS=$ORIG_CXXFLAGS
+	AC_LANG_POP(C++)
+fi
+AC_SUBST(CXX_ADD_CFLAGS)
+AC_SUBST(CXX_REMOVE_CFLAGS)
+
 #
 # Set the build profiles and options before things which use them
 #

diff --git a/mono/metadata/Makefile.am b/mono/metadata/Makefile.am
@@ -124,7 +124,8 @@ libmonoruntime_config_la_CPPFLAGS = $(AM_CPPFLAGS) -DMONO_BINDIR=\"$(bindir)/\"
 if DISABLE_ICALL_TABLES
 libmono_icall_table_la_SOURCES = \
 	icall-table.c
-libmono_icall_table_la_CFLAGS = $(SGEN_DEFINES)
+# Add CXX_ADD_CFLAGS per-library until/unless https://github.com/dotnet/corefx/pull/31342.
+libmono_icall_table_la_CFLAGS = $(SGEN_DEFINES) @CXX_ADD_CFLAGS@
 libmono_icall_table_la_LDFLAGS = $(libmonoldflags)
 if BITCODE
 libmono_icall_table_la_LIBADD = $(glib_libs) ../utils/libmonoutils.la ../sgen/libmonosgen.la libmonoruntimesgen.la
@@ -143,7 +144,8 @@ libmono_ilgen_la_SOURCES = \
 	marshal-ilgen.h	\
 	sgen-mono-ilgen.c \
 	sgen-mono-ilgen.h
-libmono_ilgen_la_CFLAGS = $(SGEN_DEFINES)
+# Add CXX_ADD_CFLAGS per-library until/unless https://github.com/dotnet/corefx/pull/31342.
+libmono_ilgen_la_CFLAGS = $(SGEN_DEFINES) @CXX_ADD_CFLAGS@
 libmono_ilgen_la_LDFLAGS = $(libmonoldflags)
 if BITCODE
 libmono_ilgen_la_LIBADD = $(glib_libs) ../utils/libmonoutils.la ../sgen/libmonosgen.la libmonoruntimesgen.la
@@ -185,7 +187,8 @@ libmono_system_native_la_SOURCES = \
 	pal-icalls.h \
 	pal-icalls.c
 
-libmono_system_native_la_CFLAGS = -I$(abs_top_srcdir)/external/corefx/src/Native/Unix/Common -I$(abs_top_srcdir)/external/corefx/src/Native/Unix/System.Native -Wno-typedef-redefinition
+# Add back CXX_REMOVE_CFLAGS to keep this as C until/unless https://github.com/dotnet/corefx/pull/31342.
+libmono_system_native_la_CFLAGS = -I$(abs_top_srcdir)/external/corefx/src/Native/Unix/Common -I$(abs_top_srcdir)/external/corefx/src/Native/Unix/System.Native -Wno-typedef-redefinition @CXX_REMOVE_CFLAGS@
 
 CLEANFILES = mono-bundle.stamp
 
@@ -404,12 +407,18 @@ sgen_sources = \
 	sgen-mono.h		\
 	sgen-client-mono.h
 
+# Per-library to workaround CoreFX/native until/unless https://github.com/dotnet/corefx/pull/31342.
+#CFLAGS := $(filter-out @CXX_REMOVE_CFLAGS@, @CFLAGS@) @CXX_ADD_CFLAGS@
+CFLAGS := $(filter-out @CXX_REMOVE_CFLAGS@, @CFLAGS@)
+
 libmonoruntime_la_SOURCES = $(common_sources) $(icall_tables_sources) $(ilgen_sources) $(gc_dependent_sources) $(null_gc_sources) $(boehm_sources)
-libmonoruntime_la_CFLAGS = $(BOEHM_DEFINES)
+# Add CXX_ADD_CFLAGS per-library until/unless https://github.com/dotnet/corefx/pull/31342.
+libmonoruntime_la_CFLAGS = $(BOEHM_DEFINES) @CXX_ADD_CFLAGS@
 libmonoruntime_la_LIBADD = libmonoruntime-config.la
 
 libmonoruntimesgen_la_SOURCES = $(common_sources) $(icall_tables_sources) $(ilgen_sources) $(gc_dependent_sources) $(sgen_sources)
-libmonoruntimesgen_la_CFLAGS = $(SGEN_DEFINES)
+# Add CXX_ADD_CFLAGS per-library until/unless https://github.com/dotnet/corefx/pull/31342.
+libmonoruntimesgen_la_CFLAGS = $(SGEN_DEFINES) @CXX_ADD_CFLAGS@
 libmonoruntimesgen_la_LIBADD = libmonoruntime-config.la
 
 libmonoruntimeincludedir = $(includedir)/mono-$(API_VER)/mono/metadata

diff --git a/mono/mini/Makefile.am.in b/mono/mini/Makefile.am.in
@@ -1005,3 +1005,4 @@ Makefile.am: Makefile.am.in $(llvm_makefile_dep)
 
 endif
 
+CFLAGS := $(filter-out @CXX_REMOVE_CFLAGS@, @CFLAGS@) @CXX_ADD_CFLAGS@
diff --git a/mono/sgen/Makefile.am b/mono/sgen/Makefile.am
@@ -63,3 +63,5 @@ monosgen_sources = \
 
 libmonosgen_la_SOURCES = $(monosgen_sources)
 libmonosgen_la_CFLAGS = $(SGEN_DEFINES)
+
+CFLAGS := $(filter-out @CXX_REMOVE_CFLAGS@, @CFLAGS@) @CXX_ADD_CFLAGS@
diff --git a/mono/utils/Makefile.am b/mono/utils/Makefile.am
@@ -318,3 +318,5 @@ DIST_SUBDIRS = jemalloc
 if MONO_JEMALLOC_ENABLED
 SUBDIRS = jemalloc
 endif
+
+CFLAGS := $(filter-out @CXX_REMOVE_CFLAGS@, @CFLAGS@) @CXX_ADD_CFLAGS@
diff --git a/scripts/ci/run-jenkins.sh b/scripts/ci/run-jenkins.sh
@@ -78,6 +78,14 @@ if [ -x "/usr/bin/dpkg-architecture" ];
 	wget -qO- https://download.mono-project.com/test/new-certs.tgz| tar zx -C ~/.config/.mono/
 fi
 
+if [[ ${CI_TAGS} == *'cxx'* ]]; then
+	EXTRA_CONF_FLAGS="$EXTRA_CONF_FLAGS -enable-cxx"
+fi
+
+if [[ ${CI_TAGS} == *'cplusplus'* ]]; then
+	EXTRA_CONF_FLAGS="$EXTRA_CONF_FLAGS -enable-cxx"
+fi
+
 if [[ ${CI_TAGS} == *'win-'* ]];
 then
 	mkdir -p ~/.config/.mono/
@@ -156,6 +164,7 @@ fi
 
 if [[ ${CI_TAGS} != *'mac-sdk'* ]]; # Mac SDK builds Mono itself
 	then
+	echo ./autogen.sh $EXTRA_CONF_FLAGS
 	${TESTCMD} --label=configure --timeout=60m --fatal ./autogen.sh $EXTRA_CONF_FLAGS
 fi
 if [[ ${CI_TAGS} == *'win-i386'* ]];
@@ -184,6 +193,20 @@ if [[ ${CI_TAGS} == *'linux-ppc64el'* ]]; then make_parallelism=-j1; fi
 make_continue=
 if [[ ${CI_TAGS} == *'checked-all'* ]]; then make_continue=-k; fi
 
+
+# FIXME For now C++ means just build mono (metadata, mini, sgen, utils) and ignore errors to get more.
+# Once this succeeds, we can let it proceed more normally through tests.
+if [[ ${CI_TAGS} == *'cxx'* ]];
+   then
+	${TESTCMD} --label=make --timeout=${make_timeout} --fatal make ${make_parallelism} -k -w -C mono V=1
+        exit 0
+fi
+if [[ ${CI_TAGS} == *'cplusplus'* ]];
+   then
+	${TESTCMD} --label=make --timeout=${make_timeout} --fatal make ${make_parallelism} -k -w -C mono V=1
+        exit 0
+fi
+
 if [[ ${CI_TAGS} != *'mac-sdk'* ]]; # Mac SDK builds Mono itself
 	then
 	${TESTCMD} --label=make --timeout=${make_timeout} --fatal make ${make_parallelism} ${make_continue} -w V=1
Original file line number	Diff line number	Diff line change
Expand Up		@@ -1005,3 +1005,4 @@ Makefile.am: Makefile.am.in $(llvm_makefile_dep)

		endif

		CFLAGS := $(filter-out @CXX_REMOVE_CFLAGS@, @CFLAGS@) @CXX_ADD_CFLAGS@
Original file line number	Diff line number	Diff line change
Expand Up		@@ -63,3 +63,5 @@ monosgen_sources = \

		libmonosgen_la_SOURCES = $(monosgen_sources)
		libmonosgen_la_CFLAGS = $(SGEN_DEFINES)

		CFLAGS := $(filter-out @CXX_REMOVE_CFLAGS@, @CFLAGS@) @CXX_ADD_CFLAGS@