first working code

```
int main() {
    long a = 0;
}
```

codegens correctly.

Cargo.lock

@@ -51,6 +51,16 @@ dependencies = [
  "smallvec",
 ]
 
+[[package]]
+name = "ariadne"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "367fd0ad87307588d087544707bc5fbf4805ded96c7db922b70d368fa1cb5702"
+dependencies = [
+ "unicode-width",
+ "yansi",
+]
+
 [[package]]
 name = "autocfg"
 version = "1.1.0"
@@ -685,6 +695,7 @@ name = "uwucc"
 version = "0.1.0"
 dependencies = [
  "analysis",
+ "ariadne",
  "bumpalo",
  "codegen",
  "dbg-pls",
@@ -759,3 +770,9 @@ checksum = "56c1936c4cc7a1c9ab21a1ebb602eb942ba868cbd44a99cb7cdc5892335e1c85"
 dependencies = [
  "linked-hash-map",
 ]
+
+[[package]]
+name = "yansi"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "09041cd90cf85f7f8b2df60c646f853b7f535ce68f85244eb6731cf89fa498ec"

Cargo.toml

@@ -14,3 +14,4 @@ analysis = { path = "./analysis" }
 codegen = { path = "./codegen" }
 parser = { path = "./parser" }
 dbg-pls = { version = "0.3.2", features = ["derive", "colors"] }
+ariadne = "0.2.0"

analysis/src/ir.rs

@@ -138,12 +138,14 @@ pub enum StatementKind {
     Store {
         ptr: Operand,
         value: Operand,
+        /// Amount of bytes to store.
         size: Operand,
         align: Operand,
     },
     Load {
         result: Register,
         ptr: Operand,
+        /// Amount of bytes to load.
         size: Operand,
         align: Operand,
     },

analysis/src/lib.rs

@@ -8,43 +8,3 @@ pub mod ty;
 
 pub use ctxt::LoweringCx;
 pub use lower::lower_translation_unit;
-use parser::Span;
-
-#[derive(Debug)]
-pub struct Error {
-    msg: String,
-    span: Option<Span>,
-    notes: Vec<Note>,
-}
-
-#[derive(Debug)]
-struct Note {
-    msg: String,
-    span: Option<Span>,
-}
-
-impl Error {
-    pub fn new(msg: impl Into<String>, span: Span) -> Self {
-        Self {
-            msg: msg.into(),
-            span: Some(span),
-            notes: Vec::new(),
-        }
-    }
-
-    pub fn new_without_span(msg: impl Into<String>) -> Self {
-        Self {
-            msg: msg.into(),
-            span: None,
-            notes: Vec::new(),
-        }
-    }
-
-    pub fn note_spanned(mut self, msg: impl Into<String>, span: Span) -> Self {
-        self.notes.push(Note {
-            msg: msg.into(),
-            span: Some(span),
-        });
-        self
-    }
-}

analysis/src/lower.rs

@@ -3,7 +3,7 @@ mod typeck;
 
 use parser::{
     ast::{self, ExprBinary},
-    Span, Symbol,
+    Error, Span, Symbol,
 };
 use rustc_hash::FxHashMap;
 
@@ -15,7 +15,6 @@ use crate::{
         VariableInfo, VariableInfoKind,
     },
     ty::{Ty, TyKind},
-    Error,
 };
 
 type Result<T, E = Error> = std::result::Result<T, E>;

analysis/src/lower/typeck.rs

@@ -1,14 +1,11 @@
 use parser::{
     ast::{IntSign, IntTy, IntTyKind},
-    Span,
+    Error, Span,
 };
 use smallvec::{smallvec, SmallVec};
 
 use super::{FnLoweringCtxt, Result};
-use crate::{
+use crate::ty::{Ty, TyKind};
-    ty::{Ty, TyKind},
-    Error,
-};
 
 pub(super) type Coercions<'cx> = SmallVec<[(Coercion, Ty<'cx>); 2]>;
 

codegen/src/lib.rs

@@ -1,5 +1,3 @@
-#![allow(unused)]
-
 mod x86_64;
 
 use std::process::Stdio;
@@ -9,8 +7,9 @@ use object::{
     elf,
     write::{Object, Symbol},
 };
+use parser::Error;
 
-type Result<T, E = analysis::Error> = std::result::Result<T, E>;
+type Result<T, E = Error> = std::result::Result<T, E>;
 
 pub fn generate<'cx>(lcx: &'cx LoweringCx<'cx>, ir: &Ir<'cx>) -> Result<()> {
     let mut obj = Object::new(
@@ -43,25 +42,24 @@ pub fn generate<'cx>(lcx: &'cx LoweringCx<'cx>, ir: &Ir<'cx>) -> Result<()> {
         obj.add_symbol(sym);
     }
 
-    let object_file = obj.write().map_err(|err| {
+    let object_file = obj
-        analysis::Error::new_without_span(format!("failed to create object file: {err}"))
+        .write()
-    })?;
+        .map_err(|err| Error::new_without_span(format!("failed to create object file: {err}")))?;
 
     std::fs::write("main.o", object_file).map_err(|err| {
-        analysis::Error::new_without_span(format!("failed to write object file main.o: {err}"))
+        Error::new_without_span(format!("failed to write object file main.o: {err}"))
     })?;
 
     let output = std::process::Command::new("cc")
         .arg("main.o")
+        .arg("-g")
         .stdout(Stdio::inherit())
         .stderr(Stdio::inherit())
         .output()
-        .map_err(|err| analysis::Error::new_without_span(format!("failed to spawn `cc`: {err}")))?;
+        .map_err(|err| Error::new_without_span(format!("failed to spawn `cc`: {err}")))?;
 
     if !output.status.success() {
-        return Err(analysis::Error::new_without_span(format!(
+        return Err(Error::new_without_span(format!("linking with `cc` failed")));
-            "linking with `cc` failed"
-        )));
     } else {
         // std::fs::remove_file("main.o").map_err(|err| {
         //     analysis::Error::new_without_span(format!(

codegen/src/x86_64.rs

@@ -65,29 +65,31 @@
 //! | %r12-r14 | callee-saved registers | Yes |
 //! | %r15     | callee-saved register; optionally used as GOT base pointer | Yes |
 
+#![allow(unused_variables, dead_code)]
+
 use analysis::{
-    ir::{self, BbIdx, Func, Location, Operand, Register, Statement, StatementKind},
+    ir::{self, BbIdx, Branch, Func, Location, Operand, Register, Statement, StatementKind},
     LoweringCx,
 };
 use iced_x86::{
     code_asm::{self as x, CodeAssembler},
-    IcedError,
+    Formatter, IcedError, NasmFormatter,
 };
-use parser::Span;
+use parser::{Error, Span};
 use rustc_hash::FxHashMap;
 
 use crate::Result;
 
 trait IcedErrExt {
     type T;
-    fn sp(self, span: Span) -> Result<Self::T, analysis::Error>;
+    fn sp(self, span: Span) -> Result<Self::T, Error>;
 }
 
 impl<T> IcedErrExt for Result<T, IcedError> {
     type T = T;
 
-    fn sp(self, span: Span) -> Result<Self::T, analysis::Error> {
+    fn sp(self, span: Span) -> Result<Self::T, Error> {
-        self.map_err(|e| analysis::Error::new(e.to_string(), span))
+        self.map_err(|e| Error::new(e.to_string(), span))
     }
 }
 
@@ -97,9 +99,13 @@ struct MachineReg(usize);
 
 #[derive(Debug, Clone, Copy)]
 enum RegValue {
+    /// The SSA register contains an address on the stack.
+    /// The offest is the offset from the start of the function.
+    StackRelative { offset: u64 },
     /// The SSA register resides on the stack as it has been spilled.
-    Stack { offset: u64 },
+    /// This should be rather rare in practice.
-    /// The SSA register resides in a machine register
+    Spilled { offset: u64 },
+    /// The SSA register resides in a machine register.
     MachineReg(MachineReg),
 }
 
@@ -143,7 +149,8 @@ impl<'cx> AsmCtxt<'cx> {
 
     fn generate_func(&mut self, func: &Func<'cx>) -> Result<()> {
         // TODO: Prologue
-        self.a.push(x::rbx);
+        self.a.push(x::rbx).sp(func.def_span)?;
+        self.a.push(x::rsp).sp(func.def_span)?;
 
         loop {
             let bb = &func.bbs[self.bb_idx.as_usize()];
@@ -159,6 +166,7 @@ impl<'cx> AsmCtxt<'cx> {
                         size,
                         align: _,
                     } => {
+                        // For alloca, we allocate some space on the stack by subtracting from RSP.
                         // TODO: Align
                         match size {
                             Operand::Const(c) => {
@@ -166,11 +174,13 @@ impl<'cx> AsmCtxt<'cx> {
                                 self.a.sub(x::rsp, offset).sp(st_sp)?;
                                 self.current_stack_offset += offset as u64;
                             }
-                            Operand::Reg(_) => todo!("dynamic alloca is not supported"),
+                            Operand::Reg(_) => {
+                                todo!("dynamic alloca is not supported. get a better computer")
+                            }
                         };
                         self.reg_map.insert(
                             reg,
-                            RegValue::Stack {
+                            RegValue::StackRelative {
                                 offset: self.current_stack_offset,
                             },
                         );
@@ -180,26 +190,44 @@ impl<'cx> AsmCtxt<'cx> {
                         value,
                         size,
                         align,
-                    } => match ptr {
+                    } => {
-                        Operand::Const(_) => todo!("const stores not implemented"),
+                        let Operand::Const(size) = size else {
-                        Operand::Reg(reg) => {
+                            todo!("non const size");
-                            let value = self.reg_map[&reg];
+                        };
-                            let stack_offset = match value {
+                        if size.as_i32() != 8 {
-                                RegValue::Stack { offset } => offset,
+                            todo!("stores of less or more than 8 bytes: {size}");
-                                RegValue::MachineReg(_) => todo!("machine reg"),
-                            };
-                            //let rhs = match value {
-                            //    Operand::Const(c) => {}
-                            //    Operand::Reg(reg) => {}
-                            //};
-
-                            // mov [rbp + OFFSET], RHS
-
-                            //self.a.add_instruction(Instruction::with2(Code::Mov, op0, op1))
-
-                            self.a.mov(x::ptr(x::rax), x::rbx);
                         }
-                    },
+                        match ptr {
+                            Operand::Const(_) => todo!("const stores not implemented"),
+                            Operand::Reg(reg) => {
+                                let ptr_value = self.reg_map[&reg];
+                                match (ptr_value, value) {
+                                    (RegValue::StackRelative { offset }, Operand::Const(c)) => {
+                                        let offset_from_cur = self.current_stack_offset - offset;
+                                        dbg!(offset_from_cur, c);
+
+                                        self.a
+                                            .mov(x::qword_ptr(x::rsp + offset_from_cur), c.as_i32())
+                                            .sp(st_sp)?;
+                                    }
+                                    (RegValue::StackRelative { offset }, Operand::Reg(value)) => {
+                                        todo!("stack relative ptr + reg value")
+                                    }
+                                    (RegValue::Spilled { .. }, _) => todo!("spilled"),
+                                    (RegValue::MachineReg(_), _) => todo!("machine reg"),
+                                };
+                                //let rhs = match value {
+                                //    Operand::Const(c) => {}
+                                //    Operand::Reg(reg) => {}
+                                //};
+
+                                // mov [rsp + OFFSET], RHS
+
+                                //self.a.add_instruction(Instruction::with2(Code::Mov, op0, op1))
+                                // self.a.mov(x::ptr(x::rax), x::rbx).sp(st_sp);
+                            }
+                        }
+                    }
                     StatementKind::Load {
                         result,
                         ptr,
@@ -228,7 +256,20 @@ impl<'cx> AsmCtxt<'cx> {
                 }
             }
 
-            todo!("next bbs");
+            match bb.term {
+                Branch::Ret(_) => {
+                    self.a
+                        .add(x::rsp, i32::try_from(self.current_stack_offset).unwrap())
+                        .sp(func.def_span)?;
+                    self.a.pop(x::rsp).sp(func.def_span)?;
+                    self.a.pop(x::rbx).sp(func.def_span)?;
+                    self.a.mov(x::rax, 0_u64).sp(func.def_span)?;
+                    self.a.ret().sp(func.def_span)?;
+                    break;
+                }
+                Branch::Switch { .. } => todo!("switch"),
+                Branch::Goto(_) => todo!("goto"),
+            }
         }
 
         Ok(())
@@ -239,7 +280,7 @@ pub fn generate_func<'cx>(lcx: &'cx LoweringCx<'cx>, func: &Func<'cx>) -> Result
     assert_eq!(func.arity, 0, "arguments??? in MY uwucc????");
 
     let fn_sp = func.def_span;
-    let mut a = CodeAssembler::new(64).sp(fn_sp)?;
+    let a = CodeAssembler::new(64).sp(fn_sp)?;
 
     let mut cx = AsmCtxt {
         lcx,
@@ -255,5 +296,14 @@ pub fn generate_func<'cx>(lcx: &'cx LoweringCx<'cx>, func: &Func<'cx>) -> Result
 
     let code = cx.a.assemble(0x4000).sp(fn_sp)?;
 
+    print!("{}:\n---", func.name);
+    let mut output = String::new();
+    let mut formatter = NasmFormatter::new();
+    for instr in cx.a.instructions() {
+        output.push('\n');
+        formatter.format(instr, &mut output);
+    }
+    println!("{output}\n---");
+
     Ok(code)
 }

flake.nix

@@ -27,6 +27,7 @@
             llvmPackages_16.bintools
             rustup
             cargo-insta
+            gdb
           ];
 
           shellHook = ''

parser/src/lib.rs

@@ -4,8 +4,8 @@
 use std::fmt::Debug;
 
 use ast::TranslationUnit;
+use dbg_pls::DebugPls;
 
-use self::parser::ParserError;
 use crate::token::Token;
 
 pub mod ast;
@@ -63,12 +63,63 @@ impl Debug for Span {
     }
 }
 
+
+#[derive(Debug)]
+pub struct Error {
+    pub msg: String,
+    pub span: Option<Span>,
+    pub notes: Vec<Note>,
+}
+
+#[derive(Debug)]
+pub struct Note {
+    pub msg: String,
+    pub span: Option<Span>,
+}
+
+impl Error {
+    pub fn new(msg: impl Into<String>, span: Span) -> Self {
+        Self {
+            msg: msg.into(),
+            span: Some(span),
+            notes: Vec::new(),
+        }
+    }
+
+    pub fn new_without_span(msg: impl Into<String>) -> Self {
+        Self {
+            msg: msg.into(),
+            span: None,
+            notes: Vec::new(),
+        }
+    }
+
+    pub fn note_spanned(mut self, msg: impl Into<String>, span: Span) -> Self {
+        self.notes.push(Note {
+            msg: msg.into(),
+            span: Some(span),
+        });
+        self
+    }
+}
+
+
+impl DebugPls for Error {
+    fn fmt(&self, f: dbg_pls::Formatter<'_>) {
+        f.debug_struct("Error")
+            .field("span", &self.span)
+            .field("msg", &self.msg)
+            .finish();
+    }
+}
+
+
 fn lex_and_pre(src: &str) -> impl Iterator<Item = (Token<'_>, Span)> + '_ {
     let pre_tokens = pre::preprocess_tokens(src);
     token::pre_tokens_to_tokens(pre_tokens)
 }
 
-pub fn parse_file(src: &str) -> Result<TranslationUnit, ParserError> {
+pub fn parse_file(src: &str) -> Result<TranslationUnit, Error> {
     let lexer = lex_and_pre(src);
     parser::parse_declarations(lexer)
 }

parser/src/parser.rs

@@ -1,4 +1,3 @@
-use dbg_pls::{DebugPls, Formatter};
 use peekmore::PeekMoreIterator;
 
 use crate::{
@@ -10,41 +9,22 @@ use crate::{
     pre::Punctuator as P,
     sym::Symbol,
     token::{Keyword as Kw, Token as Tok},
-    Span, Spanned,
+    Error, Span, Spanned,
 };
 
 mod expr;
 
-#[derive(Debug)]
+impl Error {
-pub struct ParserError {
-    span: Span,
-    message: String,
-}
-
-impl ParserError {
-    fn new(span: Span, message: String) -> Self {
-        Self { span, message }
-    }
-
     fn eof() -> Self {
-        Self::new(Span::default(), "unexpected end of file".to_string())
+        Self::new("unexpected end of file", Span::default())
     }
 
     fn unsupported(span: Span, token: &Tok<'_>) -> Self {
-        Self::new(span, format!("`{token}` is not supported"))
+        Self::new(format!("`{token}` is not supported"), span)
     }
 }
 
-impl DebugPls for ParserError {
+type Result<T, E = Error> = std::result::Result<T, E>;
-    fn fmt(&self, f: Formatter<'_>) {
-        f.debug_struct("ParserError")
-            .field("span", &self.span)
-            .field("message", &self.message)
-            .finish();
-    }
-}
-
-type Result<T, E = ParserError> = std::result::Result<T, E>;
 
 pub struct Parser<'src, I>
 where
@@ -59,12 +39,12 @@ macro_rules! expect_parser {
         match $self.next_t()? {
             ($pat, span) => span,
             (token, span) => {
-                return Err(ParserError::new(
+                return Err(Error::new(
-                    span,
                     format!(
                         concat!("expected `", stringify!($pat), "`, found {}"),
                         token
                     ),
+                    span,
                 ))
             }
         }
@@ -126,23 +106,23 @@ where
     }
 
     fn next_t(&mut self) -> Result<(Tok<'src>, Span)> {
-        self.lex.next().ok_or_else(ParserError::eof)
+        self.lex.next().ok_or_else(Error::eof)
     }
 
     fn peek_t(&mut self) -> Result<&(Tok<'src>, Span)> {
-        self.lex.peek().ok_or_else(ParserError::eof)
+        self.lex.peek().ok_or_else(Error::eof)
     }
 
     fn peek_t_n(&mut self, n: usize) -> Result<&(Tok<'src>, Span)> {
-        self.lex.peek_nth(n).ok_or_else(ParserError::eof)
+        self.lex.peek_nth(n).ok_or_else(Error::eof)
     }
 
     fn ident(&mut self) -> Result<Ident> {
         match self.next_t()? {
             (Tok::Ident(ident), span) => Ok((Symbol::intern(ident), span)),
-            (tok, span) => Err(ParserError::new(
+            (tok, span) => Err(Error::new(
-                span,
                 format!("expected identifier, found `{tok}`"),
+                span,
             )),
         }
     }
@@ -176,7 +156,7 @@ where
     /// This does NOT eat the semicolon!
     fn declaration(&mut self) -> Result<Spanned<Decl>> {
         if let Some((tok, span)) = eat!(self, Tok::Kw(Kw::StaticAssert)) {
-            return Err(ParserError::unsupported(span, &tok));
+            return Err(Error::unsupported(span, &tok));
         }
 
         let (decl_spec, span) = self.decl_specifiers()?;
@@ -264,7 +244,7 @@ where
                 // (6.7.5) alignment-specifier:
                 Tok::Kw(Kw::Alignas) => {
                     let (token, span) = self.next_t()?;
-                    return Err(ParserError::unsupported(span, &token));
+                    return Err(Error::unsupported(span, &token));
                 }
                 // if it's neither of the above, it has to be a type-specifier
                 _ => {
@@ -319,10 +299,7 @@ where
                 }
                 Tok::Kw(Kw::Signed) => {
                     if signedness.is_some() {
-                        return Err(ParserError::new(
+                        return Err(Error::new("cannot specify signedness twice", span));
-                            span,
-                            "cannot specify signedness twice".to_string(),
-                        ));
                     }
                     if let Ok((Tok::Kw(Kw::Char | Kw::Short | Kw::Int | Kw::Long), _)) =
                         self.peek_t()
@@ -335,10 +312,7 @@ where
                 }
                 Tok::Kw(Kw::Unsigned) => {
                     if signedness.is_some() {
-                        return Err(ParserError::new(
+                        return Err(Error::new("cannot specify signedness twice", span));
-                            span,
-                            "cannot specify signedness twice".to_string(),
-                        ));
                     }
                     if let Ok((Tok::Kw(Kw::Char | Kw::Short | Kw::Int | Kw::Long), _)) =
                         self.peek_t()
@@ -355,12 +329,9 @@ where
                     TypeSpecifier::Integer(IntTy(IntSign::Unsigned, IntTyKind::Bool))
                 }
                 Tok::Kw(Kw::Complex) => {
-                    return Err(ParserError::new(
+                    return Err(Error::new("tf are you doing with complex numbers", span))
-                        span,
-                        "tf are you doing with complex numbers".to_string(),
-                    ))
                 }
-                tok => return Err(ParserError::new(span, format!("Invalid token: `{tok}`"))),
+                tok => return Err(Error::new(format!("Invalid token: `{tok}`"), span)),
             };
 
             break Ok((ty, span));
@@ -413,7 +384,7 @@ where
                     // the wrong way around because borrowing
                     if let (Tok::Punct(P::ParenClose), _) = self.peek_t_n(1)? {
                         if let &(ref tok @ Tok::Kw(Kw::Void), span) = self.peek_t()? {
-                            return Err(ParserError::unsupported(span, tok));
+                            return Err(Error::unsupported(span, tok));
                         }
                     }
                 }

parser/src/parser/expr.rs

@@ -7,7 +7,7 @@ use crate::{
         ArithOpKind, Atom, BinaryOp, ComparisonKind, Expr, ExprBinary, ExprPostfix, ExprUnary,
         PostfixOp, UnaryOp,
     },
-    parser::{eat, expect, Parser, ParserError, Result},
+    parser::{eat, expect, Error, Parser, Result},
     pre::Punctuator as P,
     sym::Symbol,
     token::{Constant, Token as Tok},
@@ -40,7 +40,7 @@ where
             }
             &(Tok::Punct(punct), span) => {
                 let r_bp = prefix_binding_power(&Tok::Punct(punct)).ok_or_else(|| {
-                    ParserError::new(span, format!("expected expression, found {punct}"))
+                    Error::new(format!("expected expression, found {punct}"), span)
                 })?;
                 let Some(op) = unary_op_from_token(&Tok::Punct(punct)) else { panic!() };
                 let rhs = self.expr_bp(r_bp)?;
@@ -56,9 +56,9 @@ where
                 ));
             }
             (tok, span) => {
-                return Err(ParserError::new(
+                return Err(Error::new(
-                    *span,
                     format!("expected expression, found {tok}"),
+                    *span,
                 ));
             }
         };

parser/src/parser/tests.rs

@@ -1,12 +1,12 @@
 use super::Tok;
-use crate::{ast::ExternalDecl, parser::ParserError, Span, Spanned};
+use crate::{ast::ExternalDecl, parser::Error, Span, Spanned};
 
 fn lex_and_pre(src: &str) -> impl Iterator<Item = (Tok<'_>, Span)> + '_ {
     let pre_tokens = crate::pre::preprocess_tokens(src);
     crate::token::pre_tokens_to_tokens(pre_tokens)
 }
 
-fn pretty_print(ast: &Result<Vec<Spanned<ExternalDecl>>, ParserError>) -> String {
+fn pretty_print(ast: &Result<Vec<Spanned<ExternalDecl>>, Error>) -> String {
     let mut vec = Vec::new();
 
     match ast {

src/main.rs

@@ -1,4 +1,5 @@
 use analysis::LoweringCx;
+use parser::Error;
 
 fn main() {
     let input_file = std::env::args().nth(1).expect("first argument");
@@ -8,25 +9,52 @@ fn main() {
     });
 
     let ast = parser::parse_file(&src);
-    dbg_pls::color!(&ast);
+    // dbg_pls::color!(&ast);
-    let Ok(ast) = ast else {
+    let ast = ast.unwrap_or_else(|err| report_fatal(&input_file, &src, err));
-        std::process::exit(1);
-    };
     let mut printer = parser::pretty::PrettyPrinter::new(std::io::stdout().lock(), false);
-    println!("// START CODE  -------------------");
+    println!("-------- AST pretty");
     printer.translation_unit(&ast).unwrap();
-    println!("// END CODE    -------------------");
 
     let arena = bumpalo::Bump::new();
     let mut lcx = LoweringCx::new(&arena);
 
-    let ir = analysis::lower_translation_unit(&mut lcx, &ast).unwrap_or_else(|err| {
+    println!("-------- IR");
-        dbg!(err);
+    let ir = analysis::lower_translation_unit(&mut lcx, &ast)
-        std::process::exit(1);
+        .unwrap_or_else(|err| report_fatal(&input_file, &src, err));
-    });
 
-    codegen::generate(&lcx, &ir).unwrap_or_else(|err| {
+    println!("-------- ASM");
-        dbg!(err);
+    codegen::generate(&lcx, &ir).unwrap_or_else(|err| report_fatal(&input_file, &src, err));
-        std::process::exit(1);
+}
-    });
+
+fn report_fatal(filename: &str, source: &str, error: Error) -> ! {
+    use ariadne::{Label, Report, ReportKind, Source};
+
+    let line = match error.span {
+        Some(span) => {
+            let mut line = 0;
+            source.char_indices().find(|(i, c)| {
+                if *c == '\n' {
+                    line += 1;
+                }
+                // exit if we have found the start
+                *i >= span.start
+            });
+            line
+        }
+        None => 0,
+    };
+
+    let mut rep = Report::build(ReportKind::Error, filename, line).with_message(&error.msg);
+
+    if let Some(span) = error.span {
+        rep = rep
+            .with_label(Label::new((filename, span.start..span.end)))
+            .with_message(&error.msg);
+    }
+
+    rep.finish()
+        .eprint((filename, Source::from(source)))
+        .unwrap();
+
+    std::process::exit(1);
 }