C.

A programming language compiler written in C++ which is definitely not finished. It compile the C. code to LLVM IR.

Advantages

• simple C-like language
• blazingly fast compile times
• predictable name-mangling
• compiler less than 1.6MB stripped, ≈53MB not stripped
• classes support
• goto support
• automatic casting
• generics and closures
• rust-like pattern matching
• gc and manual memory management
• extremely fast linking (mold used by default)
• includes a clang-based C compiler, an ar-like archiver and the lld linker (like zig)

Cloning the git repo

To clone the git repo, run

git clone --recurse-submodules https://github.com/Vinz2008/C.

How to Build

Essential Dependencies

• gcc
• make
• llvm 18.x*
• clang
• lld
• autotools and libtool (for bdwgc)
• gettext (except in windows)
• tomlplusplus (for cpoint-build)

Optional Dependencies

• tar (for creating tarball releases)
• pandoc (for man pages)
• groff (for man pages)

*LLVM version used. The recommended LLVM version is 18.x. (17.x could work, but it is not garenteed to work without some edits in the code or disabling some flags)

Build Instructions

make
sudo make install

(You can add -j$(nproc) to make the build parallel)

Build Statically the compiler

How to build statically the compiler

WASM support

You can compile C. code to wasm using the -target-triplet wasm32-unknown-wasi option

TODO

• Generics support
• Importing structs with function members
• Finish refactoring the code for operators to make it compatible with every types
• Make redeclarations just the equal operator
• Fix array members and array member redeclaration bugs
• Maybe verify and warn in the manual allocation module in the standard library if an address was already freed by verifying in a list
• Add type checking in separate file and remove implicit cast and only have explicit casts with the "cast" keyword
• Add rust-styled enums with match
• Add a syntax to import every cpoint files in package
• Add chained struct members
• Add chained else if
• Add unions support in import
• Add enum support in import
• Add automatically when calling panic the file and line number to panic call
• Work on imports of template structs (for now in single file project you could include them) ( a way to fix problems with linking problems when generating the template would be to namespace the template with the filename)
• Add macro functions (for example with a syntax like #function())
• Make if, for and while return values like in rust
• Move preprocessing to import stage
• Deduplicate identical strings when creating them by keeping them in a hashmap when generating them
• Add the string version of the expression in the expect macro
• Add rust-like "traits" for simple types like i32 or float (It will be called "members" and not traits but it will be the same : add methods to types, but it will need to make the '.' an operator)
• Add number variable support to match (using it like a switch in c)
• Add static struct declaration (like with arrays) like in C ((struct struct_example){val1, val2})
• Use precompiled header for the compiler code to speed up compilation (problem : https://stackoverflow.com/questions/9580058/in-gcc-can-precompiled-headers-be-included-from-other-headers)
• Remove constructors in the language (to make it rust-like) ?
• Add members to structs with "members" blocks
• Add recursive install for binaries with subprojects with cpoint-build
• In cpoint-build, find subdependencies, compile them and link them
• Warn about/Remove unused functions
• In cpoint-build, find libraries linked to dependencies and link them
• Add "-compile-time-sizeof" flag to have sizeof not use getelementptr and the compiler insert the values at compile time
• Have specific flags for optimizations (ex : -optimize-return) or checking (-check-arrays) and global flags (-O2, -C0 for checking level 0)
• maybe create a config file to have specific profile for flags (you could have -build-mode fast-no-opti with custom profile that would be defined in the config)
• Make comments in structs, enums, etc work
• Add custom numbers for enum without types included (example : variant being 0x200 or 0x100)
• Make va_args work in C. (maybe reimplement printfmt in c and compare the generated assemblies : see it with objdump -S)
• Implement dbg macro
• Automatically make additional args in variadic functions i32s ? (for now it works without)
• Add hex notation (example 0x77)
• Add section selection for global variables
• use by default in for loop ints for the variable and then add the possibility to set the type manually
• Create a print/printfmt macro that will print vars/values .have using it be like #print("{} {}", a, 2), which will generate printfmt("%s %d", a, 2) by detecting types
• Create a println macro equivalent to #print but adding automatically a '\n' at the end of the line
• Make no_gc work (see gc.c)
• Add a little toml file in the std location to track if the latest build has the same options (no_gc, target, etc) as the current one to see if it is needed to rebuild the standard library
• Make no gc subprojects in cpoint-build be build first, then the gc ones or the other way to have the standard library rebuilt max 2 times
• Make custom values for enums work even with only the first set like in C (those after are just incremented by 1 each time, ex : the first is set manually to 2, so the second is 3, the third is 4, etc)
• Generate typedefed structs in bindgen
• Add a custom file written in cpoint to do complex builds (like build.rs or build.zig) (it could give infos using the stdout like rust does)
• Make declarations private with private keyword (it will just be passed by the lexer) or even blocks (pass private blocks in the same way as mod blocks in imports)
• Only generate the externs when functions are called
• Make import work on struct templates (copy the functions instead of generating externs) (see test21.cpoint)
• Make no_gc work directly with the cpoint compiler without cpoint-build (then make "make run" have -no-gc in the Makefile)
• Make bools returned by operators and in for loops,etc i1s and not doubles
• Add stripping mode to the compiler and the build system
• rerun benchmarks using hyperfine
• Implement closures (lambdas) (use llvm trampoline : useful link)
• Make closure captured vars usable in the closure (have a "is closure" flag for when doing the codegen of a closure) needing to use a struct named "closure" (if you need var a, you put "closure.a")
• Maybe in closure automatically generate the struct member code for the variables to use them transparently (if you need var a, you just put "a")
• Make multithreaded cpoint-build
• Work on from-c translator
• Cache object files in cpoint-build (compare timestamps of source files and object files to see if the file is needed to be compiled)
• Add syntax for input and outputs of variables in inline assembly like in Rust (https://doc.rust-lang.org/nightly/rust-by-example/unsafe/asm.html, https://doc.rust-lang.org/nightly/reference/inline-assembly.html)
• Generate unreachables with unreachable (unreachable macro ?)
• Add "-backend" flag to select the backend (for also adding a libgccjit flag)
• Add help flag (-h) to cpoint and cpoint-build
• Implement a eprintln equivalent (writing to stderr)
• Work on adding the sret attribute when needed to follow the x86 abi calling convention
• Add folder selection in cpoint-build (like in make -C)
• Add running test in cpoint-build
• Run automatically clang and create a out.o file for the c translator
• Replace sret store instruction with llvm.memcpy
• Move everything about the abi (valist, sret, byval) in an abi.cpp file
• ENABLE CLANG-FORMAT
• Implement a format macro (like the format! macro in rust)
• Add REPL
• Add mold linker support to cpoint-build (and the linker driver in the cpoint exe ?)
• Work on core library like in rust (make built-in types modules like i32 be imported by default)
• Add support in members block for built-in types like i32
• Make members block work in imports
• Replace float and double with f32 and f64 ?
• Rename list to vec or vector in std
• Add a config file for default compiler flags, etc (and add a env var like CPOINTFLAGS ?)
• Fix error messages (wrong location, wrong line, etc)
• Refactor JIT code
• Work on an arena allocator
• Work on defer (to have memory management like in zig ?)
• Make scopes expressions so you can declare scopes anywhere (ex : let a = { printd(2); var b = 2; b + 1})
• Make variable work with scopes
• Finish making all expression containing Body (vectors of ExprAST) using only an expression that can be a scope expression
• Fix cpoint-run which runs an old version of the code
• add const ptr and const types (const should be in type system)
• fix the bug with bindgen that makes const ptr args not be written in prototypes
• Remove int because it already exists ? (and create an alias in core so you can use the alias but there would not be int_type and i32_type in the compiler, only i32_type)
• Replace all ExprAST->clone()->codegen()->getType() with just ExprAST->get_type()
• Add noalias/align/dereferenceable/nonnull to function arguments and return values
• Detect when a reordering of struct members (like does rust automatically is necessary) and do an informative warning about that
• Fix bug with global variable in custom section with no default initializer
• Create a way to cross-compile easily the compiler (target prefix on gcc ? clang when cross compiling ? clang by default ?)
• Make closure private to file (like static functions in c)
• Split codegen.cpp (and ast.cpp ?) in match.cpp, closures.cpp, etc
• Make every string translated in french (and other languages ?) with gettext
• Refactor big functions in ast.cpp and codegen.cpp as smaller functions
• Replace all uses emptyLoc by the real loc passed to the function
• Add debuginfos
• Add cc and ar like zig cc
• Add thread sanitizer (https://github.com/ziglang/zig/blob/master/src/zig_llvm.cpp#L307)
• Add thread sanitizer to cpoint-build
• Add noreturn return value (return void and add the noreturn attribute to the function)
• Remove protos for not existent functions from FunctionProtos (for example if there is a struct s with a member f, there will be the s__f and the f protos in it)
• Make it possible to link llvm statically to the compiler
• Fix bug when returning from function in if and else branch
• Add lld to the compiler (like in zig)
• Force default values to variables (maybe have in the future a default trait/function member like in rust)
• Extend preprocessor functionalities (default vars, operators, else, etc)
• Add a flag to only preprocess (-E ?)
• Create website for the programming language (use cssg ? svelte ?)
• Replace LogError with assert in verification that are garanteed to be true unless there is a bug in the compiler
• Replace the globals variables by contexts (lexer context, compiler context that are global or passed to functions)
• Get the target data layout from llvm (create functions for that) to get the alignement to calculate the reordering needed for struct members
• Desactivate the warning for the struct reordering (especially in the std with struct that are accessible to C) (add extern before the struct or repr C after the struct keyword)
• Add warnings for unused labels (and unused functions ?)
• Make warnings longer (for example the warnings about the types not being the same in operators)
• Replace some verification for identifiers by keywords verification
• Add a custom cli flag for default repr for structs
• Add vector types for simd
• Add inout in inline asm args
• Make functions that are not static static if needed
• Add '...' to Constant Vectors exprs so the other numbers in the vectors would be the same as the last
• Add selecting functionalities of cpu in cli (ex : avx)
• Add a way to select the real linkname of a function in a string (like in rust) (it will help with intrisics : insted of hardcoding them, we could define them with another name in a file in core, ex : llvm.va_start) (even if we do that, we will still need to detect llvm intrisics because apparently it can't be called directly)
• Permit casting a vector from and to an array
• Add support for struct and arrays to println
• Implement features like in rust
• Make the compiler less dependent on LLVM, so more backend agnostic which would enable the c backend and the custom asm backend (for this, for example see the targets.h TODO)
• Make it possible to use the compiler with a non-clang linker (invoking the linker directly instead of a c compiler) (for example replace -Wl flags with normal flags. See the rustc_target in the rust project to see how they do it)
• Make a base file for each group of target in a base folder in the targets folder (like rust)
• If the cpu type is native, make llvm add the cpu features needed (https://github.com/rust-lang/rust/blob/2ccafed862f6906707a390caf180449dd64cad2e/compiler/rustc_codegen_llvm/src/llvm_util.rs#L517)
• Add an option for cpu types and features
• Add column number to debuginfos
• Add a isize and usize type that would be the same type of a pointer
• Build the std with cpoint-build by default instead of make
• Add function members to enums
• Add templates to enums
• Do type inference for enum templates
• instead of using TypeTemplateCallCodegen, have a way to replace all uses of templates types by the real type, returning an FunctionAST, structDeclarAST or a EnumDeclarAST (use a virtual function for exprs that would be called replace_templates_exprs)
• Make vars immutable by default
• Add c types (like c_type::bool to help interoperatibility with C code)
• Make types work with namespaces (structs and typedefs)
• Add inlined functions and other optimizations (like loop unrolling for for loops when we can know at compile time the number of iterations and it is low)
• Ship mold (optionally ?) so it can call it by default (or just add it as a dependency ?)
• Write a list of dependencies in this readme
• Add safe macros (like in rust, nim or crystal)
• Do typechecking before codegen so you can typecheck the template types (add traits to specify for example that you can add the type with the Add trait)
• In the compiler codebase, use enums instead of a lot of bools to simplify reading the code (ex : replace in Cpoint_Type "bool is_ptr" by "enum IsPtr is_ptr" with "enum IsPtr { IsPtr, NotPtr } ")
• Refactor generics (rename templates generics ?) to make it more complex (multiple template types, generics over a constant number, etc)
• Fix the order of basic blocks so the blocks are in the same order in the ir as the code
• Add a library (shared ? static ?) that would include the shared code for cpoint and cpoint-build (finding shared libraries, linking, etc) (call it libcpoint-utils ?)
• Add support for dynamically linking the std
• Add support for dynamically linking bdxgc (or using the host libgc)
• (Need to implement privates functions before that) make private functions use the fastcc calling conventions (they will not be called outside, so we don't need to follow the c calling convention)
• Fix bug with multiple empty line
• Add better debugging support for the compiler (put all info and warning logs and a textual representation of the ast in the log file
• Rework the AST : make imports AST nodes (that will be ignored like comments AST nodes) (and make the root of the file an AST node so you can pass the entire file to a function that will format the file -> work on a formatter)
• Make the compiler codebase be consistent for identifiers (function names, var names, etc) types (camelCase, etc)
• To make the formatter work, create AST exprs for everything in files (ex : macro calls) then create passes to desugar it to other exprs (ex : expand macros calls)
• create a textual representation that would be called Cpoint IR and could be a good way to make optimizations if it is as low level as MIR) (use https://mitchellh.com/zig/astgen to help create the IR)
• Maybe consider the preprocessed version of the code the equivalent of HIR in rust (move macro calls to this part ? -> probably too complicated, maybe only do it if the lexing and parsing code is refactored to be able to parse just the arg exprs of macros -> pass a context to getNextToken ?) (or consider HIR the AST before desugaring passes ?) (or parse the AST after the first preprocessing of the file,then expand the macros which will be what will be dumped if we need the preprocessed version, then use the already created AST for the codegen)
• Add incremental compilation by having a serialized mir (in binary form) that could be loaded from disk if the file hash (md5 is probably enough, the added security of sha-256 is not needed and could hinder performance -> a benchmark will probably be needed on multiple computer/platform because depending on the generation of the cpu, sha256 or even sha512 could be faster than md5) is the same (problem : the file could depend on interfaces from other files that could change, ex the proto of a function from another file changes, solutions : add a compiler flag to force not using the cache and assume 1. that if infos from imports necessary for compilation like function protos change, the use of the code, like function calls in this example will change so we need to do nothing 2. that it is needed to hash all files that are imported but there are disadvantages in performance and in ease of hash storage that could be stored in the filename of the cache file if there is one hash for each cache file)
• Use a flattened AST instead of unique_ptr for exprs : https://www.cs.cornell.edu/~asampson/blog/flattening.html (problems with vector of base class -> big issue because it would need to transform exprs into tagged unions)
• Fork compiler explorer (godbolt) make it work with cpoint
• Add custom macros like in rust
• Work on better tests (look at the zig and rust codebase) (either make the python test runner have more feature or create a test runner written in cpp) (separate the files testing std functionnalities and the ones testing compiler functionnalities) (add expects in tests)
• Rename expects asserts ?
• Add optional ref counting/replace the gc with ref counting
• Add unique ptrs
• Maybe replace entirely/make it possible to replace the build.toml with a build.cpoint (see jai lang)
• Implement Structures of Arrays
• Create an android app which includes the compiler and a code editor
• Fix statically link the bindgen exe
• Add the scripts to build the static LLVM in a different git repo
• Work on statically linking llvm dependencies when the compiler is built statically
• Add better reflection (access struct fields, etc)
• Work on serialization (do like serde ? : use traits, add derives ?)
• Add (enforce ?) manually defining the self arg and its types in struct members protos (so we can uses refs/ptrs/shared ptrs/unique ptrs for self and so we canhavre static functions that would just be struct members without self )
• Add calling functions in mods without specifying the mod (ex a function in the mod file will only need to use foo to call file::foo)
• Implement iterators
• Add a warning for unreachable code
• Deactivate generating out.ll and out.mir by default (and generate out.o when creating an exe in a temp dir)
• Stop using the llvm namespace to differentiate similar functions or classes from cir and to see where llvm is called to make the compiler more independent of it
• Remove all unnecessary gotos in the compiler codebase
• Have the least number of unique_ptrs (so dynamic allocation) in the codebase (ex : use only vectors and not vectors of unique_ptrs when you can, it will also optimize cache)
• Make if (expr1 && expr2) two ifs to make guards work (like clang)
• After removing the old llvm backend, replace not needed clones in the cir with std::move
• Make work the DISABLE_OLD_LLVM_BACKEND config
• Make the size of bool 8 bits
• Use an arena for allocation in the compiler
• Add the possibility to use an included binutils (in /usr/local/lib/cpoint/tools ?) to use as an assembler for the x86 backend
• Make so the makefile build a separate llvm in tree if llvm is not installed (or if manually asked) and link to it (probably statically in this case or put it in /usr/local/lib/cpoint)
• Add typechecking for casts (also differenciate depending of if the cast is implicit)
• Make the compiler work with mimalloc to improve performance
• Make backends shared libraries to remove useless shared libraries dependencies and enable lazy load backend dependencies (llvm, maybe libgccjit in the future ?)
• Use ccache if available when building the compiler (will speed up rebuilds)
• Add support for (downloading?), building and linking libc for other platforms for cross-compiling (ex : wasi, libcxx, llvm libc/musl ?)
• Simplify the command to compile the compiler for wasm
• Fix crash that happens sometimes (not all the time !) when compiling arena.cpoint in the std with optimizations on level 3 (it prints "malloc_consolidate(): unaligned fastbin chunk detected")
• Remove useless Log::Info() calls
• Add comptime/const functions
• Add a c backend using llvm-cbe after the llvm backend
• Add support for custom json target files to replace the custom targets informations like in rust (use glaze or simdjson to parse the json)

Benchmarks compared to other languages

Complete benchmarks

Length of benchmarks in seconds, lower is better

Note about the name

C. is pronounced like C point. It was named like it and not C dot or period but C point because I just named the executable cpoint without thinking about it and then remembered that it is not a transparent translation from french and that it should have been name ccomma, but hey I am too lazy to fix it ¯\(ツ)/¯

Locales

The locales are not installed by default. If you want the locales file installed on your system, run make install in the "locales" directory