add optional Clang 4.0 support for Nginx compiles in 123.09beta01

For CentOS 7 where CLANG_FOUR='y' is set in persist config file at /etc/centminmod/custom_config.inc, will enable Clang 4.0 detection support. If custom Clang 4.0 binary is detected at /opt/sbin/llvm/bin/clang, and CLANG_FOUR='y set, then Nginx will compile with Clang 4.0 instead of Clang 3.4.2 when CLANG='y' is set (default). Details https://community.centminmod.com/posts/44039/

centmin.sh

@@ -287,6 +287,7 @@ CCACHESIZE='2.2G'
 PARALLEL_MODE=y
 # compiler related
 CLANG='y'                     # Nginx and LibreSSL
+CLANG_FOUR='n'                # Clang 4.0+ optional support https://community.centminmod.com/posts/44039/
 CLANG_PHP='n'                 # PHP
 CLANG_APC='n'                 # APC Cache
 CLANG_MEMCACHED='n'           # Memcached menu option 10 routine

example/custom_config.inc

@@ -18,6 +18,7 @@ ENABLEMOTD_LINKSMSG='y'       # motd centminmod.com links bookmark alert display
 
 # Clang & GCC Compilers
 CLANG='y'                     # Nginx and LibreSSL
+CLANG_FOUR='n'                # Clang 4.0+ optional support https://community.centminmod.com/posts/44039/
 CLANG_PHP='n'                 # PHP
 CLANG_APC='n'                 # APC Cache
 CLANG_MEMCACHED='n'           # Memcached menu option 10 routine

inc/nginx_configure.inc

@@ -2008,7 +2008,36 @@ if [[ "$CLANG" = [yY] ]]; then
 	# ccache compiler has some initial overhead for compiles but speeds up subsequent
 	# recompiles. however on initial install ccache has no benefits, so for initial
 	# centmin mod install disabling ccache will in theory speed up first time installs
-	if [[ "$INITIALINSTALL" != [yY] ]]; then	
+
+if [[ "CENTOS_SEVEN" = '7' && "$CLANG_FOUR" = [yY] && -f /opt/sbin/llvm/bin/clang ]]; then
+	############################
+	if [[ "$INITIALINSTALL" != [yY] ]]; then
+		export CC="ccache /opt/sbin/llvm/bin/clang -ferror-limit=0${CCTOOLSET}"
+		export CXX="ccache /opt/sbin/llvm/bin/clang++ -ferror-limit=0"
+		export CCACHE_CPP2=yes
+		CLANG_CCOPT=' -Wno-sign-compare -Wno-string-plus-int -Wno-deprecated-declarations -Wno-unused-parameter -Wno-unused-const-variable -Wno-conditional-uninitialized -Wno-mismatched-tags -Wno-sometimes-uninitialized -Wno-parentheses-equality -Wno-tautological-compare -Wno-self-assign -Wno-deprecated-register -Wno-deprecated -Wno-invalid-source-encoding -Wno-pointer-sign -Wno-parentheses -Wno-enum-conversion -Wno-c++11-compat-deprecated-writable-strings -Wno-write-strings'
+echo "
+export CC=\"ccache /opt/sbin/llvm/bin/clang -ferror-limit=0${CCTOOLSET}\"
+export CXX=\"ccache /opt/sbin/llvm/bin/clang++ -ferror-limit=0\"
+export CCACHE_CPP2=yes
+CLANG_CCOPT=' -Wno-sign-compare -Wno-string-plus-int -Wno-deprecated-declarations -Wno-unused-parameter -Wno-unused-const-variable -Wno-conditional-uninitialized -Wno-mismatched-tags -Wno-sometimes-uninitialized -Wno-parentheses-equality -Wno-tautological-compare -Wno-self-assign -Wno-deprecated-register -Wno-deprecated -Wno-invalid-source-encoding -Wno-pointer-sign -Wno-parentheses -Wno-enum-conversion -Wno-c++11-compat-deprecated-writable-strings -Wno-write-strings'"
+	else
+		export CC="/opt/sbin/llvm/bin/clang -ferror-limit=0${CCTOOLSET}"
+		export CXX="/opt/sbin/llvm/bin/clang++ -ferror-limit=0"
+		# export CCACHE_CPP2=yes
+		CLANG_CCOPT=' -Wno-sign-compare -Wno-string-plus-int -Wno-deprecated-declarations -Wno-unused-parameter -Wno-unused-const-variable -Wno-conditional-uninitialized -Wno-mismatched-tags -Wno-sometimes-uninitialized -Wno-parentheses-equality -Wno-tautological-compare -Wno-self-assign -Wno-deprecated-register -Wno-deprecated -Wno-invalid-source-encoding -Wno-pointer-sign -Wno-parentheses -Wno-enum-conversion -Wno-c++11-compat-deprecated-writable-strings -Wno-write-strings'
+echo "	
+export CC=\"/opt/sbin/llvm/bin/clang -ferror-limit=0${CCTOOLSET}\"
+export CXX=\"/opt/sbin/llvm/bin/clang++ -ferror-limit=0\"
+# export CCACHE_CPP2=yes
+CLANG_CCOPT=' -Wno-sign-compare -Wno-string-plus-int -Wno-deprecated-declarations -Wno-unused-parameter -Wno-unused-const-variable -Wno-conditional-uninitialized -Wno-mismatched-tags -Wno-sometimes-uninitialized -Wno-parentheses-equality -Wno-tautological-compare -Wno-self-assign -Wno-deprecated-register -Wno-deprecated -Wno-invalid-source-encoding -Wno-pointer-sign -Wno-parentheses -Wno-enum-conversion -Wno-c++11-compat-deprecated-writable-strings -Wno-write-strings'"
+	fi
+	############################
+	## clang 4.0 else
+else
+	## clang 4.0 else
+	############################
+	if [[ "$INITIALINSTALL" != [yY] ]]; then
 		export CC="ccache /usr/bin/clang -ferror-limit=0${CCTOOLSET}"
 		export CXX="ccache /usr/bin/clang++ -ferror-limit=0"
 		export CCACHE_CPP2=yes
@@ -2029,6 +2058,8 @@ export CXX=\"/usr/bin/clang++ -ferror-limit=0\"
 # export CCACHE_CPP2=yes
 CLANG_CCOPT=' -Wno-sign-compare -Wno-string-plus-int -Wno-deprecated-declarations -Wno-unused-parameter -Wno-unused-const-variable -Wno-conditional-uninitialized -Wno-mismatched-tags -Wno-sometimes-uninitialized -Wno-parentheses-equality -Wno-tautological-compare -Wno-self-assign -Wno-deprecated-register -Wno-deprecated -Wno-invalid-source-encoding -Wno-pointer-sign -Wno-parentheses -Wno-enum-conversion -Wno-c++11-compat-deprecated-writable-strings -Wno-write-strings'"
 	fi
+	############################
+fi # clang 4.0
 else
 	CLANG_CCOPT=""
 	echo "CLANG_CCOPT=\"\""