1 files changed, 80 insertions, 55 deletions

diff --git a/src/codegen.cpp b/src/codegen.cpp
index 37f15f43a7..b1431a9c33 100644
--- a/src/codegen.cpp
+++ b/src/codegen.cpp
@@ -112,10 +112,10 @@ CodeGen *codegen_create(Buf *root_src_path, const ZigTarget *target, OutType out
         // that's for native compilation
         g->zig_target = *target;
         resolve_target_object_format(&g->zig_target);
-        g->dynamic_linker = buf_create_from_str("");
-        g->libc_lib_dir = buf_create_from_str("");
-        g->libc_static_lib_dir = buf_create_from_str("");
-        g->libc_include_dir = buf_create_from_str("");
+        g->dynamic_linker = nullptr;
+        g->libc_lib_dir = nullptr;
+        g->libc_static_lib_dir = nullptr;
+        g->libc_include_dir = nullptr;
         g->msvc_lib_dir = nullptr;
         g->kernel32_lib_dir = nullptr;
         g->each_lib_rpath = false;
@@ -123,16 +123,13 @@ CodeGen *codegen_create(Buf *root_src_path, const ZigTarget *target, OutType out
         // native compilation, we can rely on the configuration stuff
         g->is_native_target = true;
         get_native_target(&g->zig_target);
-        g->dynamic_linker = buf_create_from_str(ZIG_DYNAMIC_LINKER);
-        g->libc_lib_dir = buf_create_from_str(ZIG_LIBC_LIB_DIR);
-        g->libc_static_lib_dir = buf_create_from_str(ZIG_LIBC_STATIC_LIB_DIR);
-        g->libc_include_dir = buf_create_from_str(ZIG_LIBC_INCLUDE_DIR);
+        g->dynamic_linker = nullptr; // find it at runtime
+        g->libc_lib_dir = nullptr; // find it at runtime
+        g->libc_static_lib_dir = nullptr; // find it at runtime
+        g->libc_include_dir = nullptr; // find it at runtime
         g->msvc_lib_dir = nullptr; // find it at runtime
         g->kernel32_lib_dir = nullptr; // find it at runtime
-
-#ifdef ZIG_EACH_LIB_RPATH
         g->each_lib_rpath = true;
-#endif
 
         if (g->zig_target.os == OsMacOSX ||
             g->zig_target.os == OsIOS)
@@ -657,6 +654,7 @@ static ZigLLVMDIScope *get_di_scope(CodeGen *g, Scope *scope) {
         case ScopeIdDeferExpr:
         case ScopeIdLoop:
         case ScopeIdCompTime:
+        case ScopeIdCoroPrelude:
             return get_di_scope(g, scope->parent);
     }
     zig_unreachable();
@@ -1295,9 +1293,34 @@ static LLVMValueRef get_safety_crash_err_fn(CodeGen *g) {
     return fn_val;
 }
 
-static void gen_safety_crash_for_err(CodeGen *g, LLVMValueRef err_val) {
+static bool is_coro_prelude_scope(Scope *scope) {
+    while (scope != nullptr) {
+        if (scope->id == ScopeIdCoroPrelude) {
+            return true;
+        } else if (scope->id == ScopeIdFnDef) {
+            break;
+        }
+        scope = scope->parent;
+    }
+    return false;
+}
+
+static LLVMValueRef get_cur_err_ret_trace_val(CodeGen *g, Scope *scope) {
+    if (!g->have_err_ret_tracing) {
+        return nullptr;
+    }
+    if (g->cur_fn->type_entry->data.fn.fn_type_id.cc == CallingConventionAsync) {
+        return is_coro_prelude_scope(scope) ? g->cur_err_ret_trace_val_arg : g->cur_err_ret_trace_val_stack;
+    }
+    if (g->cur_err_ret_trace_val_stack != nullptr) {
+        return g->cur_err_ret_trace_val_stack;
+    }
+    return g->cur_err_ret_trace_val_arg;
+}
+
+static void gen_safety_crash_for_err(CodeGen *g, LLVMValueRef err_val, Scope *scope) {
     LLVMValueRef safety_crash_err_fn = get_safety_crash_err_fn(g);
-    LLVMValueRef err_ret_trace_val = g->cur_err_ret_trace_val;
+    LLVMValueRef err_ret_trace_val = get_cur_err_ret_trace_val(g, scope);
     if (err_ret_trace_val == nullptr) {
         TypeTableEntry *ptr_to_stack_trace_type = get_ptr_to_stack_trace_type(g);
         err_ret_trace_val = LLVMConstNull(ptr_to_stack_trace_type->type_ref);
@@ -1574,32 +1597,25 @@ static LLVMValueRef ir_llvm_value(CodeGen *g, IrInstruction *instruction) {
     return instruction->llvm_value;
 }
 
+static LLVMValueRef ir_render_save_err_ret_addr(CodeGen *g, IrExecutable *executable,
+        IrInstructionSaveErrRetAddr *save_err_ret_addr_instruction)
+{
+    assert(g->have_err_ret_tracing);
+
+    LLVMValueRef return_err_fn = get_return_err_fn(g);
+    LLVMValueRef args[] = {
+        get_cur_err_ret_trace_val(g, save_err_ret_addr_instruction->base.scope),
+    };
+    LLVMValueRef call_instruction = ZigLLVMBuildCall(g->builder, return_err_fn, args, 1,
+            get_llvm_cc(g, CallingConventionUnspecified), ZigLLVM_FnInlineAuto, "");
+    LLVMSetTailCall(call_instruction, true);
+    return call_instruction;
+}
+
 static LLVMValueRef ir_render_return(CodeGen *g, IrExecutable *executable, IrInstructionReturn *return_instruction) {
     LLVMValueRef value = ir_llvm_value(g, return_instruction->value);
     TypeTableEntry *return_type = return_instruction->value->value.type;
 
-    if (g->have_err_ret_tracing) {
-        bool is_err_return = false;
-        if (return_type->id == TypeTableEntryIdErrorUnion) {
-            if (return_instruction->value->value.special == ConstValSpecialStatic) {
-                is_err_return = return_instruction->value->value.data.x_err_union.err != nullptr;
-            } else if (return_instruction->value->value.special == ConstValSpecialRuntime) {
-                is_err_return = return_instruction->value->value.data.rh_error_union == RuntimeHintErrorUnionError;
-                // TODO: emit a branch to check if the return value is an error
-            }
-        } else if (return_type->id == TypeTableEntryIdErrorSet) {
-            is_err_return = true;
-        }
-        if (is_err_return) {
-            LLVMValueRef return_err_fn = get_return_err_fn(g);
-            LLVMValueRef args[] = {
-                g->cur_err_ret_trace_val,
-            };
-            LLVMValueRef call_instruction = ZigLLVMBuildCall(g->builder, return_err_fn, args, 1,
-                    get_llvm_cc(g, CallingConventionUnspecified), ZigLLVM_FnInlineAuto, "");
-            LLVMSetTailCall(call_instruction, true);
-        }
-    }
     if (handle_is_ptr(return_type)) {
         if (calling_convention_does_first_arg_return(g->cur_fn->type_entry->data.fn.fn_type_id.cc)) {
             assert(g->cur_ret_ptr);
@@ -2671,7 +2687,7 @@ static LLVMValueRef ir_render_call(CodeGen *g, IrExecutable *executable, IrInstr
         gen_param_index += 1;
     }
     if (prefix_arg_err_ret_stack) {
-        gen_param_values[gen_param_index] = g->cur_err_ret_trace_val;
+        gen_param_values[gen_param_index] = get_cur_err_ret_trace_val(g, instruction->base.scope);
         gen_param_index += 1;
     }
     if (instruction->is_async) {
@@ -3238,11 +3254,12 @@ static LLVMValueRef ir_render_align_cast(CodeGen *g, IrExecutable *executable, I
 static LLVMValueRef ir_render_error_return_trace(CodeGen *g, IrExecutable *executable,
         IrInstructionErrorReturnTrace *instruction)
 {
-    if (g->cur_err_ret_trace_val == nullptr) {
+    LLVMValueRef cur_err_ret_trace_val = get_cur_err_ret_trace_val(g, instruction->base.scope);
+    if (cur_err_ret_trace_val == nullptr) {
         TypeTableEntry *ptr_to_stack_trace_type = get_ptr_to_stack_trace_type(g);
         return LLVMConstNull(ptr_to_stack_trace_type->type_ref);
     }
-    return g->cur_err_ret_trace_val;
+    return cur_err_ret_trace_val;
 }
 
 static LLVMValueRef ir_render_cancel(CodeGen *g, IrExecutable *executable, IrInstructionCancel *instruction) {
@@ -3648,7 +3665,7 @@ static LLVMValueRef ir_render_unwrap_err_payload(CodeGen *g, IrExecutable *execu
         LLVMBuildCondBr(g->builder, cond_val, ok_block, err_block);
 
         LLVMPositionBuilderAtEnd(g->builder, err_block);
-        gen_safety_crash_for_err(g, err_val);
+        gen_safety_crash_for_err(g, err_val, instruction->base.scope);
 
         LLVMPositionBuilderAtEnd(g->builder, ok_block);
     }
@@ -3840,7 +3857,7 @@ static LLVMValueRef ir_render_container_init_list(CodeGen *g, IrExecutable *exec
 }
 
 static LLVMValueRef ir_render_panic(CodeGen *g, IrExecutable *executable, IrInstructionPanic *instruction) {
-    gen_panic(g, ir_llvm_value(g, instruction->msg), g->cur_err_ret_trace_val);
+    gen_panic(g, ir_llvm_value(g, instruction->msg), get_cur_err_ret_trace_val(g, instruction->base.scope));
     return nullptr;
 }
 
@@ -4127,6 +4144,7 @@ static LLVMValueRef ir_render_instruction(CodeGen *g, IrExecutable *executable,
         case IrInstructionIdSetRuntimeSafety:
         case IrInstructionIdSetFloatMode:
         case IrInstructionIdArrayType:
+        case IrInstructionIdPromiseType:
         case IrInstructionIdSliceType:
         case IrInstructionIdSizeOf:
         case IrInstructionIdSwitchTarget:
@@ -4167,6 +4185,7 @@ static LLVMValueRef ir_render_instruction(CodeGen *g, IrExecutable *executable,
         case IrInstructionIdErrorUnion:
         case IrInstructionIdPromiseResultType:
         case IrInstructionIdAwaitBookkeeping:
+        case IrInstructionIdAddImplicitReturnType:
             zig_unreachable();
 
         case IrInstructionIdReturn:
@@ -4315,6 +4334,8 @@ static LLVMValueRef ir_render_instruction(CodeGen *g, IrExecutable *executable,
             return ir_render_coro_alloc_helper(g, executable, (IrInstructionCoroAllocHelper *)instruction);
         case IrInstructionIdAtomicRmw:
             return ir_render_atomic_rmw(g, executable, (IrInstructionAtomicRmw *)instruction);
+        case IrInstructionIdSaveErrRetAddr:
+            return ir_render_save_err_ret_addr(g, executable, (IrInstructionSaveErrRetAddr *)instruction);
     }
     zig_unreachable();
 }
@@ -5197,9 +5218,17 @@ static void do_code_gen(CodeGen *g) {
         clear_debug_source_node(g);
 
         uint32_t err_ret_trace_arg_index = get_err_ret_trace_arg_index(g, fn_table_entry);
-        if (err_ret_trace_arg_index != UINT32_MAX) {
-            g->cur_err_ret_trace_val = LLVMGetParam(fn, err_ret_trace_arg_index);
-        } else if (g->have_err_ret_tracing && fn_table_entry->calls_or_awaits_errorable_fn) {
+        bool have_err_ret_trace_arg = err_ret_trace_arg_index != UINT32_MAX;
+        if (have_err_ret_trace_arg) {
+            g->cur_err_ret_trace_val_arg = LLVMGetParam(fn, err_ret_trace_arg_index);
+        } else {
+            g->cur_err_ret_trace_val_arg = nullptr;
+        }
+
+        bool is_async = fn_table_entry->type_entry->data.fn.fn_type_id.cc == CallingConventionAsync;
+        bool have_err_ret_trace_stack = g->have_err_ret_tracing && fn_table_entry->calls_or_awaits_errorable_fn &&
+            (is_async || !have_err_ret_trace_arg);
+        if (have_err_ret_trace_stack) {
             // TODO call graph analysis to find out what this number needs to be for every function
             static const size_t stack_trace_ptr_count = 30;
 
@@ -5207,13 +5236,13 @@ static void do_code_gen(CodeGen *g) {
             TypeTableEntry *array_type = get_array_type(g, usize, stack_trace_ptr_count);
             LLVMValueRef err_ret_array_val = build_alloca(g, array_type, "error_return_trace_addresses",
                     get_abi_alignment(g, array_type));
-            g->cur_err_ret_trace_val = build_alloca(g, g->stack_trace_type, "error_return_trace", get_abi_alignment(g, g->stack_trace_type));
+            g->cur_err_ret_trace_val_stack = build_alloca(g, g->stack_trace_type, "error_return_trace", get_abi_alignment(g, g->stack_trace_type));
             size_t index_field_index = g->stack_trace_type->data.structure.fields[0].gen_index;
-            LLVMValueRef index_field_ptr = LLVMBuildStructGEP(g->builder, g->cur_err_ret_trace_val, (unsigned)index_field_index, "");
+            LLVMValueRef index_field_ptr = LLVMBuildStructGEP(g->builder, g->cur_err_ret_trace_val_stack, (unsigned)index_field_index, "");
             gen_store_untyped(g, LLVMConstNull(usize->type_ref), index_field_ptr, 0, false);
 
             size_t addresses_field_index = g->stack_trace_type->data.structure.fields[1].gen_index;
-            LLVMValueRef addresses_field_ptr = LLVMBuildStructGEP(g->builder, g->cur_err_ret_trace_val, (unsigned)addresses_field_index, "");
+            LLVMValueRef addresses_field_ptr = LLVMBuildStructGEP(g->builder, g->cur_err_ret_trace_val_stack, (unsigned)addresses_field_index, "");
 
             TypeTableEntry *slice_type = g->stack_trace_type->data.structure.fields[1].type_entry;
             size_t ptr_field_index = slice_type->data.structure.fields[slice_ptr_index].gen_index;
@@ -5229,7 +5258,7 @@ static void do_code_gen(CodeGen *g) {
             LLVMValueRef len_field_ptr = LLVMBuildStructGEP(g->builder, addresses_field_ptr, (unsigned)len_field_index, "");
             gen_store(g, LLVMConstInt(usize->type_ref, stack_trace_ptr_count, false), len_field_ptr, get_pointer_to_type(g, usize, false));
         } else {
-            g->cur_err_ret_trace_val = nullptr;
+            g->cur_err_ret_trace_val_stack = nullptr;
         }
 
         // allocate temporary stack data
@@ -6172,7 +6201,7 @@ static ImportTableEntry *add_special_code(CodeGen *g, PackageTableEntry *package
         zig_panic("unable to open '%s': %s", buf_ptr(&path_to_code_src), err_str(err));
     }
     Buf *import_code = buf_alloc();
-    if ((err = os_fetch_file_path(abs_full_path, import_code))) {
+    if ((err = os_fetch_file_path(abs_full_path, import_code, false))) {
         zig_panic("unable to open '%s': %s", buf_ptr(&path_to_code_src), err_str(err));
     }
 
@@ -6260,7 +6289,7 @@ static void gen_root_source(CodeGen *g) {
     }
 
     Buf *source_code = buf_alloc();
-    if ((err = os_fetch_file_path(rel_full_path, source_code))) {
+    if ((err = os_fetch_file_path(rel_full_path, source_code, true))) {
         zig_panic("unable to open '%s': %s", buf_ptr(rel_full_path), err_str(err));
     }
 
@@ -6325,7 +6354,7 @@ static void gen_global_asm(CodeGen *g) {
     int err;
     for (size_t i = 0; i < g->assembly_files.length; i += 1) {
         Buf *asm_file = g->assembly_files.at(i);
-        if ((err = os_fetch_file_path(asm_file, &contents))) {
+        if ((err = os_fetch_file_path(asm_file, &contents,  false))) {
             zig_panic("Unable to read %s: %s", buf_ptr(asm_file), err_str(err));
         }
         buf_append_buf(&g->global_asm, &contents);
@@ -6507,6 +6536,7 @@ static void get_c_type(CodeGen *g, GenH *gen_h, TypeTableEntry *type_entry, Buf
                 }
             }
         case TypeTableEntryIdStruct:
+        case TypeTableEntryIdOpaque:
             {
                 buf_init_from_str(out_buf, "struct ");
                 buf_append_buf(out_buf, &type_entry->name);
@@ -6524,11 +6554,6 @@ static void get_c_type(CodeGen *g, GenH *gen_h, TypeTableEntry *type_entry, Buf
                 buf_append_buf(out_buf, &type_entry->name);
                 return;
             }
-        case TypeTableEntryIdOpaque:
-            {
-                buf_init_from_buf(out_buf, &type_entry->name);
-                return;
-            }
         case TypeTableEntryIdArray:
             {
                 TypeTableEntryArray *array_data = &type_entry->data.array;