protobuf3-cpp: build with cmake; compatibility ver change requires de…

…p rebuilds

- Provides cmake build files for dependents, among other benefits

devel/protobuf3-cpp/Portfile

@@ -3,6 +3,7 @@
 PortSystem      1.0
 PortGroup       compiler_blacklist_versions 1.0
 PortGroup       github 1.0
+PortGroup       cmake 1.1
 
 # NOTE: For any version number change, also
 # NOTE:   Update py-protobuf3 version's number to match
@@ -15,7 +16,7 @@ name            protobuf3-cpp
 github.setup    protocolbuffers protobuf 3.${release_version} v
 git.branch      v${release_version}
 # remove stealth update code below with next update
-revision        1
+revision        2
 
 # remove stealth update code with next update
 dist_subdir     ${name}/${version}_1
@@ -53,25 +54,40 @@ github.tarball_from releases
 distname        protobuf-cpp-${version}
 worksrcdir      protobuf-${version}
 
+# Upstream adds zlib include - which is ${prefix}/include - before search path
+# of 3rd-party components, like gtest, gmock, etc. That causes the external
+# versions of those to be pulled in, and the build fails.
+# So don't let the project cmake add zlib; already added (last) by base.
+patchfiles-append cmake-zlib-include.diff
+
 compiler.cxx_standard   2011
 compiler.thread_local_storage   yes
 # error: constexpr constructor never produces a constant expression [-Winvalid-constexpr]
 compiler.blacklist {clang < 900}
 
-# bundled libtool version doesn't recognise -stdlib
-use_autoreconf  yes
+if { [string match *clang* ${configure.compiler}] } {
+    # Quiet deprecation warnings
+    configure.cxxflags-append \
+                -Wno-deprecated-declarations \
+                -Wno-error=unknown-warning-option \
+                -Wno-unknown-warning-option
+}
 
-# see https://trac.macports.org/wiki/UsingTheRightCompiler
-configure.env-append \
-    CC_FOR_BUILD=${configure.cc} \
-    CXX_FOR_BUILD=${configure.cxx}
+# Clear optflags; controlled by project, via cmake build type
+configure.optflags
 
-configure.cflags-append     -g
-configure.cppflags-append   -g
+if {[variant_isset debug]} {
+    cmake.build_type Debug
+} else {
+    cmake.build_type RelWithDebInfo
+}
 
 depends_lib-append \
                 port:zlib
 
+configure.args-append \
+                -DBUILD_SHARED_LIBS:BOOL=ON
+
 post-destroot {
     set docdir ${destroot}${prefix}/share/doc/${name}