a32abcd365
if expressions no longer introduce a stack allocation.
```zig
export fn entry() void {
var x: anyerror!i32 = 1234;
if (x) |i| {} else |e| {}
}
```
```llvm
define void @entry() #2 !dbg !39 {
Entry:
%x = alloca { i16, i32 }, align 4
%0 = bitcast { i16, i32 }* %x to i8*, !dbg !52
call void @llvm.memcpy.p0i8.p0i8.i64(i8* align 4 %0, i8* align 4 bitcast ({ i16, i32 }* @0 to i8*), i64 8, i1 false), !dbg !52
call void @llvm.dbg.declare(metadata { i16, i32 }* %x, metadata !43, metadata !DIExpression()), !dbg !52
%1 = getelementptr inbounds { i16, i32 }, { i16, i32 }* %x, i32 0, i32 0, !dbg !53
%2 = load i16, i16* %1, align 2, !dbg !53
%3 = icmp ne i16 %2, 0, !dbg !53
br i1 %3, label %TryElse, label %TryOk, !dbg !53
TryOk: ; preds = %Entry
%4 = getelementptr inbounds { i16, i32 }, { i16, i32 }* %x, i32 0, i32 1, !dbg !53
call void @llvm.dbg.declare(metadata i32* %4, metadata !50, metadata !DIExpression()), !dbg !53
br label %TryEnd, !dbg !53
TryElse: ; preds = %Entry
%5 = getelementptr inbounds { i16, i32 }, { i16, i32 }* %x, i32 0, i32 0, !dbg !53
call void @llvm.dbg.declare(metadata i16* %5, metadata !51, metadata !DIExpression()), !dbg !53
br label %TryEnd, !dbg !53
TryEnd: ; preds = %TryElse, %TryOk
ret void, !dbg !54
}
```
Zig is an open-source programming language designed for robustness, optimality, and maintainability.
Resources
Building from Source
Note that you can download a binary of master branch.
Stage 1: Build Zig from C++ Source Code
Dependencies
POSIX
- cmake >= 2.8.5
- gcc >= 5.0.0 or clang >= 3.6.0
- LLVM, Clang, LLD development libraries == 8.x, compiled with the same gcc or clang version above
- Use the system package manager, or build from source.
Windows
- cmake >= 2.8.5
- Microsoft Visual Studio 2017 (version 15.8)
- LLVM, Clang, LLD development libraries == 8.x, compiled with the same MSVC version above
- Use the pre-built binaries or build from source.
Instructions
POSIX
mkdir build
cd build
cmake ..
make install
MacOS
brew install cmake llvm@8
brew outdated llvm@8 || brew upgrade llvm@8
mkdir build
cd build
cmake .. -DCMAKE_PREFIX_PATH=/usr/local/Cellar/llvm/8.0.0
make install
Windows
See https://github.com/ziglang/zig/wiki/Building-Zig-on-Windows
Stage 2: Build Self-Hosted Zig from Zig Source Code
Note: Stage 2 compiler is not complete. Beta users of Zig should use the Stage 1 compiler for now.
Dependencies are the same as Stage 1, except now you can use stage 1 to compile Zig code.
bin/zig build --build-file ../build.zig --prefix $(pwd)/stage2 install
This produces ./stage2/bin/zig which can be used for testing and development.
Once it is feature complete, it will be used to build stage 3 - the final compiler
binary.
Stage 3: Rebuild Self-Hosted Zig Using the Self-Hosted Compiler
Note: Stage 2 compiler is not yet able to build Stage 3. Building Stage 3 is not yet supported.
Once the self-hosted compiler can build itself, this will be the actual compiler binary that we will install to the system. Until then, users should use stage 1.
Debug / Development Build
./stage2/bin/zig build --build-file ../build.zig --prefix $(pwd)/stage3 install
Release / Install Build
./stage2/bin/zig build --build-file ../build.zig install -Drelease-fast