From c42763f8cc9223fc43ac3478a5f15d4bd9f438e4 Mon Sep 17 00:00:00 2001
From: Andrew Kelley <andrew@ziglang.org>
Date: Wed, 24 Nov 2021 14:47:33 -0700
Subject: [PATCH] AstGen: use reachableExpr for return operand

Related: #9630
---
 lib/std/math/ln.zig     | 2 +-
 lib/std/math/log.zig    | 2 +-
 lib/std/math/log10.zig  | 2 +-
 lib/std/math/log2.zig   | 2 +-
 lib/std/math/sqrt.zig   | 2 +-
 src/AstGen.zig          | 2 +-
 test/compile_errors.zig | 9 +++++++++
 7 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/lib/std/math/ln.zig b/lib/std/math/ln.zig
index d2a5ae807e..bb352cd6e1 100644
--- a/lib/std/math/ln.zig
+++ b/lib/std/math/ln.zig
@@ -32,7 +32,7 @@ pub fn ln(x: anytype) @TypeOf(x) {
             return @as(comptime_int, math.floor(ln_64(@as(f64, x))));
         },
         .Int => |IntType| switch (IntType.signedness) {
-            .signed => return @compileError("ln not implemented for signed integers"),
+            .signed => @compileError("ln not implemented for signed integers"),
             .unsigned => return @as(T, math.floor(ln_64(@as(f64, x)))),
         },
         else => @compileError("ln not implemented for " ++ @typeName(T)),
diff --git a/lib/std/math/log.zig b/lib/std/math/log.zig
index cab652c620..6336726b39 100644
--- a/lib/std/math/log.zig
+++ b/lib/std/math/log.zig
@@ -29,7 +29,7 @@ pub fn log(comptime T: type, base: T, x: T) T {
 
         // TODO implement integer log without using float math
         .Int => |IntType| switch (IntType.signedness) {
-            .signed => return @compileError("log not implemented for signed integers"),
+            .signed => @compileError("log not implemented for signed integers"),
             .unsigned => return @floatToInt(T, math.floor(math.ln(@intToFloat(f64, x)) / math.ln(float_base))),
         },
 
diff --git a/lib/std/math/log10.zig b/lib/std/math/log10.zig
index 19602fb4a2..84eced85f0 100644
--- a/lib/std/math/log10.zig
+++ b/lib/std/math/log10.zig
@@ -33,7 +33,7 @@ pub fn log10(x: anytype) @TypeOf(x) {
             return @as(comptime_int, math.floor(log10_64(@as(f64, x))));
         },
         .Int => |IntType| switch (IntType.signedness) {
-            .signed => return @compileError("log10 not implemented for signed integers"),
+            .signed => @compileError("log10 not implemented for signed integers"),
             .unsigned => return @floatToInt(T, math.floor(log10_64(@intToFloat(f64, x)))),
         },
         else => @compileError("log10 not implemented for " ++ @typeName(T)),
diff --git a/lib/std/math/log2.zig b/lib/std/math/log2.zig
index fca941c49a..556c16f5cf 100644
--- a/lib/std/math/log2.zig
+++ b/lib/std/math/log2.zig
@@ -39,7 +39,7 @@ pub fn log2(x: anytype) @TypeOf(x) {
             return result;
         },
         .Int => |IntType| switch (IntType.signedness) {
-            .signed => return @compileError("log2 not implemented for signed integers"),
+            .signed => @compileError("log2 not implemented for signed integers"),
             .unsigned => return math.log2_int(T, x),
         },
         else => @compileError("log2 not implemented for " ++ @typeName(T)),
diff --git a/lib/std/math/sqrt.zig b/lib/std/math/sqrt.zig
index d54063dcf6..871cc58e47 100644
--- a/lib/std/math/sqrt.zig
+++ b/lib/std/math/sqrt.zig
@@ -26,7 +26,7 @@ pub fn sqrt(x: anytype) Sqrt(@TypeOf(x)) {
             return @as(T, sqrt_int(u128, x));
         },
         .Int => |IntType| switch (IntType.signedness) {
-            .signed => return @compileError("sqrt not implemented for signed integers"),
+            .signed => @compileError("sqrt not implemented for signed integers"),
             .unsigned => return sqrt_int(T, x),
         },
         else => @compileError("sqrt not implemented for " ++ @typeName(T)),
diff --git a/src/AstGen.zig b/src/AstGen.zig
index 7132dc07ef..ae66cae662 100644
--- a/src/AstGen.zig
+++ b/src/AstGen.zig
@@ -5963,7 +5963,7 @@ fn ret(gz: *GenZir, scope: *Scope, node: Ast.Node.Index) InnerError!Zir.Inst.Ref
     } else .{
         .ty = try gz.addNodeExtended(.ret_type, node),
     };
-    const operand = try expr(gz, scope, rl, operand_node);
+    const operand = try reachableExpr(gz, scope, rl, operand_node, node);
 
     switch (nodeMayEvalToError(tree, operand_node)) {
         .never => {
diff --git a/test/compile_errors.zig b/test/compile_errors.zig
index 6240fae587..1a3e81e176 100644
--- a/test/compile_errors.zig
+++ b/test/compile_errors.zig
@@ -4999,6 +4999,15 @@ pub fn addCases(ctx: *TestContext) !void {
         "tmp.zig:2:5: note: control flow is diverted here",
     });
 
+    ctx.objErrStage1("unreachable code - return return",
+        \\export fn a() i32 {
+        \\    return return 1;
+        \\}
+    , &[_][]const u8{
+        "tmp.zig:2:5: error: unreachable code",
+        "tmp.zig:2:12: note: control flow is diverted here",
+    });
+
     ctx.objErrStage1("bad import",
         \\const bogus = @import("bogus-does-not-exist.zig",);
     , &[_][]const u8{