https://github.com/tjensen42/makefiles
Some simple Makefiles for compiling C/C++ with auto dependency generation. Feel free to use them as template.
https://github.com/tjensen42/makefiles
c compile cpp dependencies makefile makefile-template
Last synced: 12 months ago
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Some simple Makefiles for compiling C/C++ with auto dependency generation. Feel free to use them as template.
- Host: GitHub
- URL: https://github.com/tjensen42/makefiles
- Owner: tjensen42
- Created: 2022-07-25T11:07:46.000Z (over 3 years ago)
- Default Branch: master
- Last Pushed: 2022-08-25T06:48:58.000Z (over 3 years ago)
- Last Synced: 2025-03-28T07:51:09.512Z (about 1 year ago)
- Topics: c, compile, cpp, dependencies, makefile, makefile-template
- Homepage:
- Size: 43 KB
- Stars: 7
- Watchers: 1
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
Awesome Lists containing this project
README
# Makefile templates
## Variables
```Makefile
NAME := # Executable name
CC := # Program for compiling C programs; default ‘cc’
CFLAGS := # Extra flags to give to the C compiler
CXX := # Program for compiling C++ programs
CXXFLAGS := # Extra flags to give to the C++ compiler
CPPFLAGS := # Extra flags to give to the C preprocessor and programs that use it
DEPFLAGS = # Specific flags which convince the compiler to generate the dependency file
LDFLAGS := # Linker flags, path where to search for library: -L./libft
LDLIBS := # Library flags or names: -lm -lft
VPATH := # A list of directories to be searched for source files: ./src/ ./src/parser
SRCS := # specify all source files (*.c)
ODIR := # Dir for .o files (object files)
OBJS := # $(SRCS:%.c=$(ODIR)/%.o) get object files from src files
DDIR := # Dir for .d files (dependency files)
DEPS := # $(SRCS:%.c=$(DDIR)/%.d) get dep files from src files
```
## Auto dependency generation
* https://make.mad-scientist.net/papers/advanced-auto-dependency-generation/
(dependency flags explained at the bottom of the page)
### Overview:
```Makefile
# Set the name of the target in the generated dependency file.
-MT $@
# Generate dependency information as a side-effect of compilation, not instead of compilation. This version omits system headers from the generated dependencies: if you prefer to preserve system headers as prerequisites, use -MD.
-MMD
# Adds a target for each prerequisite in the list, to avoid errors when deleting files.
-MP
# Write the generated dependency file $(DEPDIR)/$*.d.
-MF $(DEPDIR)/$*.d
# Generate list of dependency files
DEPS := $(SRCS:%.c=$(DEPDIR)/%.d)
# Declare the generated dependency file as a prerequisite of the target, so that if it’s missing the target will be rebuilt.
... $(DEPDIR)/%.d
# Declare the dependency directory as an order-only prerequisite of the target, so that it will be created when needed.
... | $(DEPDIR)
# Declare a rule for creating the dependency directory if it doesn’t exist:
$(DEPDIR): ; @mkdir -p $@
# Mention each dependency file as a target, so that make won’t fail if the file doesn’t exist.
$(DEPFILES):
# Include the dependency files that exist
-include $(DEPS)
```
## Linux warn_unused_result fix
```Makefile
# **************************************************************************** #
# SYSTEM SPECIFIC SETTINGS #
# **************************************************************************** #
ifeq ($(shell uname -s), Linux)
CFLAGS += -Wno-unused-result
endif
```
## Parallel compilation with make -j
```bash
# It is recommended to use number of CPU cores for the num_of_processes
make -j
```
```Makefile
# Makefile builtin approach
UNAME := $(shell uname -s)
NUMPROC := 8
ifeq ($(UNAME), Linux)
NUMPROC := $(shell grep -c ^processor /proc/cpuinfo)
else ifeq ($(UNAME), Darwin)
NUMPROC := $(shell sysctl -n hw.ncpu)
endif
all:
@$(MAKE) $(NAME) -j$(NUMPROC)
```