From 0d1969024c6fd7fa9aa729cf17860d0c172b56e0 Mon Sep 17 00:00:00 2001
From: Michael Forney <mforney@mforney.org>
Date: Mon, 12 Aug 2019 01:53:46 -0700
Subject: Revert "expr: Fix cast of same type"

This reverts commit 1a38a5fc4844a0de8729be694a62ba0afce3ff52.

This breaks comparisons bitfields in some cases, for instance

	extern struct {unsigned x:31;} s;
	int main(void) {
		return (unsigned)s.x - 1 < 0;
	}

If we discard the cast, then it is a signed comparison because of integer
promotion for bit-fields, otherwise it is an unsigned comparison.

Additionally, the test case this was meant to fix is not actually ISO C,
since casts must be to scalar types or `void`.
---
 test/cast-same-type.qbe | 12 ------------
 1 file changed, 12 deletions(-)
 delete mode 100644 test/cast-same-type.qbe

(limited to 'test')

diff --git a/test/cast-same-type.qbe b/test/cast-same-type.qbe
deleted file mode 100644
index 625f937..0000000
--- a/test/cast-same-type.qbe
+++ /dev/null
@@ -1,12 +0,0 @@
-export
-function w $main() {
-@start.1
-@body.2
-	%.1 =l copy $s
-	%.2 =l mul 0, 1
-	%.3 =l add %.1, %.2
-	%.4 =l copy %.3
-	%.5 =w loadsw %.4
-	ret %.5
-}
-export data $s = align 4 { z 4 }
-- 
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