Open MPI with CXX headers installation test file with generic Makefile

main.cpp

#include <iostream>
#include <memory>
#include <vector>

#include <mpicxx.h>

int main() {
  MPI::Init();

  const auto world_size = MPI::COMM_WORLD.Get_size();
  const auto world_rank = MPI::COMM_WORLD.Get_rank();

  auto name = std::vector<char>(MPI_MAX_PROCESSOR_NAME, std::allocator<char>());
  auto name_size = 0;
  MPI::Get_processor_name(&name[0], name_size);

  std::cout << "Hello, world! From processor " << &name[0] << ", rank " << world_rank + 1 << "/" << world_size
            << std::endl;

  MPI::Finalize();

  return 0;
}

Makefile

BIN?=main
OMPI_CC=clang++ mpic++
MPICXX?=mpic++
MPIRUN?=mpirun
EXT?=cpp
LINKS?=
NB_SLOTS?=2


SRCS=$(shell find . -name "*."$(EXT))
DIRS=$(shell find ./* -type d)
OBJS=$(patsubst %.$(EXT),%.o,$(SRCS))
INCS=$(addprefix -I, $(DIRS))

CPPFLAGS+=-std=c++17 -Wall $(INCS)
LDFLAGS+=$(addprefix -l, $(LINKS))

.PHONY: all run clean

all: $(BIN)

$(EXT).o: $(SRCS)
	$(CXX) $(CPPFLAGS) -c $<

$(BIN): $(OBJS)
	$(MPICXX) $(CPPFLAGS) -o $(BIN) $(notdir $(OBJS)) $(LDFLAGS)

run: all
	-$(MPIRUN) ./$(BIN)

runn: all
	-$(MPIRUN) -n $(NB_SLOTS) ./$(BIN)

clean:
	-rm -f $(notdir $(OBJS)) $(BIN)