Fixed libomp use on clang and darwin. Usage and comments in pull request.

configure

@@ -691,6 +691,10 @@ X_PRE_LIBS
 X_CFLAGS
 CPP
 XMKMF
+falcon_OPENMP_LINKFLAGS
+falcon_OPENMP_CXXFLAGS
+OPENMP_LINKFLAGS
+OPENMP_CXXFLAGS
 falcon_OPENMP
 STDFLAG
 MAKEDIRS
@@ -1492,7 +1496,7 @@ Optional Packages:
   --with-ccmalloc         use CCMALLOC for malloc
   --with-dso              use DSO linking
   --with-opt              use opt for essentials
-  --with-openmp           use OMP directives
+  --with-openmp           use OMP directives; mac/clang only: path to libomp
   --with-std              use this -std=
   --with-x                use the X Window System
   --with-pgplot-prefix=DIR   Directory where PGPLOT was installed, aka PGPLOT_DIR
@@ -6763,16 +6767,47 @@ else
 fi
 
 
-if test $with_openmp = "yes"; then
-  CFLAGS="$CFLAGS -fopenmp"
-  CXXFLAGS="$CXXFLAGS -fopenmp"
-  FFLAGS="$CFLAGS -fopenmp"
+OPENMP_CXXFLAGS=""
+OPENMP_LINKFLAGS=""
+falcon_OPENMP="noOPENMP"
+if test $with_openmp != "no"; then
   falcon_OPENMP="OPENMP"
-else
-  falcon_OPENMP="noOPENMP"
+  if ${CC} --version | grep -q "clang"; then
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether we have a valid libomp path" >&5
+printf %s "checking whether we have a valid libomp path... " >&6; }
+    if ! (test -d "$with_openmp/lib" && test -d "$with_openmp/include"); then
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: No libomp path" >&5
+printf "%s\n" "$as_me: WARNING: No libomp path" >&2;}
+      echo "*********************************************************************************"
+      echo " You are compiling on clang (either directly or because you're on OS X)"
+      echo " and included a --with-openmp option, but did not provide a path to a "
+      echo " valid libomp install. Unlike other c compilers, clang does not include"
+      echo " libomp.  You'll need to install libomp yourself with something like brew."
+      echo " Note also that brew will not symlink libomp from within /usr/*/lib, citing"
+      echo " possible damage to the OS.  You'll need to know the path to the parent"
+      echo " dir of include/libomp.h and lib/libomp.* and provide it with the --with-openmp"
+      echo " option, e.g.:"
+      echo "      /.configure ... --with-openmp=~/mybrew/Cellar/libomp/18.0.1"
+      echo "*********************************************************************************"
+    else
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
+      OPENMP_CXXFLAGS="-Xclang -fopenmp -I$with_openmp/include "
+      OPENMP_LINKFLAGS="-L$with_openmp/lib -lomp "
+    fi
+  else
+    OPENMP_CXXFLAGS="-fopenmp"
+  fi
 fi
 
 
+
+falcon_OPENMP_CXXFLAGS="$OPENMP_CXXFLAGS"
+falcon_OPENMP_LINKFLAGS="$OPENMP_LINKFLAGS"
+
+
+
+
 ac_ext=c
 ac_cpp='$CPP $CPPFLAGS'
 ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'

configure.ac

@@ -246,7 +246,7 @@ AC_ARG_WITH(dso,
 AC_ARG_WITH(opt, 
 		  [  --with-opt              use opt for essentials], with_opt=$withval, with_opt=no)
 AC_ARG_WITH(openmp,
-		  [  --with-openmp           use OMP directives], with_openmp=$withval, with_openmp=no)
+		  [  --with-openmp           use OMP directives; mac/clang only: path to libomp ], with_openmp=$withval, with_openmp=no)
 
 AC_ARG_WITH(std,
 		  [  --with-std              use this -std=], with_std=$withval, with_std=c99)
@@ -258,15 +258,43 @@ else
 fi
 AC_SUBST(STDFLAG)
 
-if test $with_openmp = "yes"; then
-  CFLAGS="$CFLAGS -fopenmp"
-  CXXFLAGS="$CXXFLAGS -fopenmp"
-  FFLAGS="$CFLAGS -fopenmp"
+OPENMP_CXXFLAGS=""
+OPENMP_LINKFLAGS=""
+falcon_OPENMP="noOPENMP"
+if test $with_openmp != "no"; then
   falcon_OPENMP="OPENMP"
-else
-  falcon_OPENMP="noOPENMP"
+  if ${CC} --version | grep -q "clang"; then
+    AC_MSG_CHECKING([whether we have a valid libomp path])
+    if ! (test -d "$with_openmp/lib" && test -d "$with_openmp/include"); then
+      AC_MSG_WARN([No libomp path])
+      echo "*********************************************************************************"
+      echo " You are compiling on clang (either directly or because you're on OS X)"
+      echo " and included a --with-openmp option, but did not provide a path to a "
+      echo " valid libomp install. Unlike other c compilers, clang does not include"
+      echo " libomp.  You'll need to install libomp yourself with something like brew."
+      echo " Note also that brew will not symlink libomp from within /usr/*/lib, citing"
+      echo " possible damage to the OS.  You'll need to know the path to the parent"
+      echo " dir of include/libomp.h and lib/libomp.* and provide it with the --with-openmp"
+      echo " option, e.g.:"
+      echo "      /.configure [...] --with-openmp=~/mybrew/Cellar/libomp/18.0.1"
+      echo "*********************************************************************************"
+    else
+      AC_MSG_RESULT([yes])
+      OPENMP_CXXFLAGS="-Xclang -fopenmp -I$with_openmp/include "
+      OPENMP_LINKFLAGS="-L$with_openmp/lib -lomp "
+    fi
+  else
+    OPENMP_CXXFLAGS="-fopenmp"
+  fi
 fi
 AC_SUBST(falcon_OPENMP)
+AC_SUBST(OPENMP_CXXFLAGS)
+AC_SUBST(OPENMP_LINKFLAGS)
+falcon_OPENMP_CXXFLAGS="$OPENMP_CXXFLAGS"
+falcon_OPENMP_LINKFLAGS="$OPENMP_LINKFLAGS"
+AC_SUBST(falcon_OPENMP_CXXFLAGS)
+AC_SUBST(falcon_OPENMP_LINKFLAGS)
+
 
 dnl ---------------------------------------------------------------------
 dnl             Check for basic X windows stuff : AC_PATH_XTRA -> X_CFLAGS and X_LIBS

makedefs.in

@@ -78,6 +78,11 @@ GSL_LIB =
 PLPLOT_INC = @PLPLOT_CFLAGS@
 PLPLOT_LIB = @PLPLOT_LIBS@
 
+# OPENMP
+OPENMP_CXXFLAGS=@OPENMP_CXXFLAGS@
+OPENMP_LINKFLAGS=@OPENMP_LINKFLAGS@
+
+
 #	FFTW
 #       -lfftw3, or -lfftw3f or -lfftw3l (depending on precision library, for float or long double)
 #       [actually still not used yet]
@@ -149,10 +154,10 @@ LOPT = @LDFLAGS@
 #   for shared libaries
 CCSHARED = @CCSHARED@
 #   everything 
-CFLAGS   = $(COPT) $(CCSHARED) $(NEMO_CFLAGS) $(PFLAGS)  @STDFLAG@
-CXXFLAGS = $(COPT) $(CCSHARED) $(NEMO_CFLAGS)
+CFLAGS   = $(COPT) $(CCSHARED) $(NEMO_CFLAGS) $(PFLAGS) $(OPENMP_CXXFLAGS) @STDFLAG@
+CXXFLAGS = $(COPT) $(CCSHARED) $(NEMO_CFLAGS) $(OPENMP_CXXFLAGS)
 FFLAGS   = $(FOPT) $(CCSHARED) $(NEMO_FFLAGS)
-LDFLAGS  = $(LOPT)             $(NEMO_LDFLAGS)
+LDFLAGS  = $(LOPT)             $(NEMO_LDFLAGS) $(OPENMP_LIBFLAGS)
 CPPFLAGS = @CPPFLAGS@
 
 RANLIB = @RANLIB@

src/kernel/io/Makefile

@@ -109,7 +109,7 @@ endian: endian.c
 	$(CC) $(CFLAGS) -DTOOLBOX -o endian endian.c $(NEMO_LIBS)
 
 getpartest: getparam.c
-	$(CC) $(CFLAGS) -o getpartest -DTESTBED getparam.c $(NEMO_LIBS)
+	$(CC) $(CFLAGS) $(OPENMP_CXXFLAGS) -o getpartest -DTESTBED getparam.c $(NEMO_LIBS) $(OPENMP_LINKFLAGS)
 
 stropentest: stropen.c
 	$(CC) $(CFLAGS) -o stropentest -DTESTBED stropen.c $(NEMO_LIBS)

src/kernel/io/getparam.c

@@ -230,14 +230,14 @@
 
 
 //#if defined(ENABLE_OPENMP)
-#if _OPENMP
+//#if _OPENMP
 #include <omp.h>
 local double omp_t1, omp_t2;
 #else
 typedef int omp_int_t;
 inline omp_int_t omp_get_thread_num() { return 0;}
 inline omp_int_t omp_get_max_threads() { return 1;}
-#endif
+//#endif
 
 #if defined(TCL7)
 # include <tcl.h>

src/tutor/mp/Makefile

@@ -4,7 +4,7 @@
 CC    = gcc
 MPICC = mpicc
 
-TIME = /usr/bin/time -f "%U %S %e %P"
+TIME = /usr/bin/time
 
 include $(NEMOLIB)/makedefs
 
@@ -16,7 +16,7 @@ clean:
 	rm -f $(BINS)
 
 hello1:
-	$(CC) -fopenmp -O3  -o hello1 hellomp.c  -lm
+	$(CC) $(OPENMP_CXXFLAGS) -O3  -o hello1 hellomp.c  -lm $(OPENMP_LINKFLAGS)
 
 hello2:
 	$(CC)          -O3  -o hello2 hellomp.c  -lm
@@ -27,7 +27,7 @@ bench: $(BINS)
 
 
 heated_plate_openmp:
-	$(CC) $(CFLAGS) -fopenmp -o heated_plate_openmp heated_plate_openmp.c $(NEMO_LIBS)
+	$(CC) $(CFLAGS) $(OPENMP_CXXFLAGS) -o heated_plate_openmp heated_plate_openmp.c $(NEMO_LIBS) $(OPENMP_LINKFLAGS)
 
 bench2: heated_plate_openmp
 	$(TIME) ./heated_plate_openmp nprocs=4
@@ -48,7 +48,7 @@ bench4:
 # scaling from https://stackoverflow.com/questions/19780554/what-limits-scaling-in-this-simple-openmp-program
 
 scaling: scaling.c
-	$(CC) scaling.c -std=c99 -fopenmp -O3    -o scaling -lm
+	$(CC) scaling.c -std=c99 $(OPENMP_CXXFLAGS) -O3    -o scaling -lm $(OPENMP_LINKFLAGS)
 
 ONT=1 2 4 8 16
 bench5: scaling
@@ -58,7 +58,7 @@ bench5: scaling
 
 
 quad_openmp: quad_openmp.c
-	gcc -fopenmp quad_openmp.c -o quad_openmp
+	gcc $(OPENMP_CXXFLAGS) quad_openmp.c -o quad_openmp $(OPENMP_LINKFLAGS)
 
 bench6:  quad_openmp
 	@echo OMP_NUM_THREADS ONT=$(ONT)

usr/dehnen/falcON/src/public/lib/bodyfunc.cc

@@ -35,6 +35,7 @@
 #include <sstream>
 #include <cstring>
 #include <cstdlib>
+#include <limits>
 
 using namespace falcON;
 ////////////////////////////////////////////////////////////////////////////////
@@ -154,8 +155,8 @@ namespace {
     // compiles a falcON C++ program in fname using compiler flags              
     const char* falcON_path = falcON::directory();
     if(falcON_path == 0) throw BfErr("cannot locate falcON directory");
-    char cmmd[512];
-    SNprintf(cmmd,512,"cd /tmp; %s %s.cc -o %s.so"
+    char cmmd[PATH_MAX];
+    SNprintf(cmmd,PATH_MAX,"cd /tmp; %s %s.cc -o %s.so"
 	     " %s -shared -fPIC -I%s/inc -I%s/inc/utils -O2"
 #if __cplusplus >= 201103L
 	     " -std=c++0x"
@@ -172,14 +173,20 @@ namespace {
 	     " -DfalcON_SINGLE"
 #endif
 #if   defined(__INTEL_COMPILER)
-	     " -ip -xHost -fpic -falign-functions -openmp -g -Wall"
-
+	     " -ip -xHost -fpic -falign-functions -g -Wall"
+#     if "x$OPENMP" != "x"
+         " -openmp"
+#     endif
 	     // 	     	     " -march=native -mfpmath=sse -mpreferred-stack-boundary=4 -ggdb3"
+#elif defined(__clang__)
+	 " -mfpmath=sse -ggdb3"
+     " -Wall -Wextra -Winit-self -Wshadow -Woverloaded-virtual -fPIC"
+     " -std=c++11 -funroll-loops -fforce-addr $OPENMP_CXXFLAGS $OPENMP_LINKFLAGS"
 #elif defined(__GNUC__)
 	     " -mfpmath=sse -mpreferred-stack-boundary=4 -ggdb3"
 	     " -Wall -Wextra -Winit-self -Wshadow -Woverloaded-virtual -fPIC"
 	     " -std=c++11"
-	     " -fopenmp -funroll-loops -fforce-addr"
+	     " $OPENMP_CXXFLAGS -funroll-loops -fforce-addr $OPENMP_LINKFLAGS"
 #else
 	     " -fpic -openmp -g"
 #endif
@@ -193,8 +200,8 @@ namespace {
     if(system(cmmd)) {
       if(debug(debug_depth)) {
 	std::cerr<<"could not compile temporary file /tmp/"<<fname<<".cc:\n";
-	char show[512];
-	SNprintf(show,512,"more /tmp/%s.cc > /dev/stderr",fname);
+	char show[PATH_MAX];
+	SNprintf(show,PATH_MAX,"more /tmp/%s.cc > /dev/stderr",fname);
   int rr;
 	rr=system(show);
 	std::cerr<<"\nwith the command\n\""<<cmmd<<"\".\n"
@@ -211,8 +218,8 @@ namespace {
   inline void delete_files(const char*fname) {
     // delete files /tmp/fname.* UNLESS debug(debug_depth)
     if(delete_f && !debug(debug_depth) && fname && fname[0]) {
-      char cmmd[512];
-      SNprintf(cmmd,512,"rm -f /tmp/%s.* > /dev/null 2>&1",fname);
+      char cmmd[PATH_MAX];
+      SNprintf(cmmd,PATH_MAX,"rm -f /tmp/%s.* > /dev/null 2>&1",fname);
       DebugInfo(4,"executing \"%s\"\n",cmmd);
       int rr=system(cmmd);
     }
@@ -510,7 +517,7 @@ namespace {
       "#define BD_TEST\n"
       "#define body_func\n"
       "#include <public/bodyfuncdefs.h>\n\n"
-      "real   _P[10]={RNG()};\n\n"
+      "real   _P[10]={static_cast<real>(RNG())};\n\n"
       "extern \"C\" {\n"
       "  fieldset "<<ftype<<"(char&_type)\n"
       "  {\n"

usr/dehnen/utils/make.clang

@@ -71,9 +71,9 @@ CXXFLAGS	:= $(STDAPI) $(OPTFLAGS)
 endif
 
 ifdef OPENMP
-CXXFLAGS	+= -fopenmp
-CFLAGS		+= -fopenmp
-LDFLAGS		:= -shared -fopenmp $(PROFLAGS)
+CXXFLAGS	+= $(OPENMP_CXXFLAGS)
+CFLAGS		+= $(OPENMP_CXXFLAGS)
+LDFLAGS		:= -shared  -$(OPENMP_LINKFLAGS) $(PROFLAGS)
 else
 LDFLAGS		:= -shared $(PROFLAGS)
 endif

usr/dehnen/utils/make.gcc

@@ -99,9 +99,9 @@ CXXFLAGS	:= $(STDAPI) $(OPTFLAGS)
 endif
 
 ifdef OPENMP
-CXXFLAGS	+= -fopenmp
-CFLAGS		+= -fopenmp
-LDFLAGS		:= -shared -fopenmp $(PROFLAGS)
+CXXFLAGS	+=  $(OPENMP_CXXFLAGS)
+CFLAGS		+=  $(OPENMP_CXXFLAGS)
+LDFLAGS		:= -shared  $(OPENMP_CXXFLAGS) $(PROFLAGS)
 else
 LDFLAGS		:= -shared $(PROFLAGS)
 endif

usr/dehnen/utils/make.sh.in

@@ -8,6 +8,8 @@ NO_ARCH_NATIVE=@falcon_NO_NATIVE@
 
 # if you want --fopenmp it should say "OPENMP=1"
 @falcon_OPENMP@=1
+OPENMP_CXXFLAGS=@falcon_OPENMP_CXXFLAGS@
+OPENMP_LINKFLAGS=@falcon_OPENMP_LINKFLAGS@
 
 # do or don't do shared libs. by default no, because of SIP on mac
 NO_SHARED_LIBS=@NO_SHARED_LIBS@

usr/dehnen/utils/makefile

@@ -62,7 +62,7 @@ $(LIBT)			:
 # ---------
 
 INCLUDE			:= -I$(INC)
-LINKLIBS		+= $(CXXLIBS)
+LINKLIBS		+= $(CXXLIBS) $(OPENMP_LINKFLAGS)
 
 # math lib
 ifndef MATHLIB