From 597ead5318421befba3619fed389820d241ecc78 Mon Sep 17 00:00:00 2001
From: Cody Tapscott <topolarity@tapscott.me>
Date: Fri, 23 Sep 2022 14:40:55 -0700
Subject: [PATCH] stage2: Fix usage of getError()

Despite the old doc-comment, this function cannot be valid for all types
since it operates with only a value and Error (Union) types have
overlapping Value representations with other Types.
---
 src/Sema.zig  | 1 +
 src/value.zig | 7 ++++---
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/Sema.zig b/src/Sema.zig
index 70cff08e29..6daedd12cc 100644
--- a/src/Sema.zig
+++ b/src/Sema.zig
@@ -11107,6 +11107,7 @@ fn maybeErrorUnwrapCondbr(sema: *Sema, block: *Block, body: []const Zir.Inst.Ind
         return;
     }
     if (try sema.resolveDefinedValue(block, cond_src, err_operand)) |val| {
+        if (!operand_ty.isError()) return;
         if (val.getError() == null) return;
         try sema.maybeErrorUnwrapComptime(block, body, err_operand);
     }
diff --git a/src/value.zig b/src/value.zig
index ee5b357a70..d24c5a1c17 100644
--- a/src/value.zig
+++ b/src/value.zig
@@ -2971,9 +2971,10 @@ pub const Value = extern union {
         };
     }
 
-    /// Valid for all types. Asserts the value is not undefined and not unreachable.
-    /// Prefer `errorUnionIsPayload` to find out whether something is an error or not
-    /// because it works without having to figure out the string.
+    /// Valid only for error (union) types. Asserts the value is not undefined and not
+    /// unreachable. For error unions, prefer `errorUnionIsPayload` to find out whether
+    /// something is an error or not because it works without having to figure out the
+    /// string.
     pub fn getError(self: Value) ?[]const u8 {
         return switch (self.tag()) {
             .@"error" => self.castTag(.@"error").?.data.name,