diff --git a/ir_fold.h b/ir_fold.h
index a2d49f4..976e889 100644
--- a/ir_fold.h
+++ b/ir_fold.h
@@ -1152,6 +1152,7 @@ IR_FOLD(FP2FP(C_DOUBLE))
 /* Copy Propagation */
 IR_FOLD(COPY(_))
 {
+	IR_ASSERT(IR_OPT_TYPE(opt) == op1_insn->type);
 	if (!op2) {
 		IR_FOLD_COPY(op1);
 	}
diff --git a/tests/010.irt b/tests/010.irt
index f3162f2..028a669 100644
--- a/tests/010.irt
+++ b/tests/010.irt
@@ -11,7 +11,7 @@
 	int32_t c_5 = 2;
 	l_1 = START(l_20);
 	bool d_2 = PARAM(l_1, "cond", 0);
-	bool d_3 = COPY(c_4);
+	int32_t d_3 = COPY(c_4);
 	l_4 = END(l_1);
 	l_5 = LOOP_BEGIN(l_4, l_18);
 	int32_t d_6 = PHI(l_5, d_3, d_15);
diff --git a/tests/013.irt b/tests/013.irt
index eb33661..4444526 100644
--- a/tests/013.irt
+++ b/tests/013.irt
@@ -12,8 +12,8 @@
 	l_1 = START(l_33);
 	bool d_2 = PARAM(l_1, "cond", 0);
 	int32_t d_3 = PARAM(l_1, "z", 1);
-	bool d_4 = COPY(c_4);
-	bool d_5 = COPY(d_3);
+	int32_t d_4 = COPY(c_4);
+	int32_t d_5 = COPY(d_3);
 	l_6 = END(l_1);
 	l_7 = LOOP_BEGIN(l_6, l_31);
 	int32_t d_8 = PHI(l_7, d_4, d_19);
diff --git a/tests/016.irt b/tests/016.irt
index 4f6c171..711f0ee 100644
--- a/tests/016.irt
+++ b/tests/016.irt
@@ -11,7 +11,7 @@
 	int32_t c_5 = 2;
 	l_1 = START(l_20);
 	bool d_2 = PARAM(l_1, "cond", 0);
-	bool d_3 = COPY(c_4);
+	int32_t d_3 = COPY(c_4);
 	l_4 = END(l_1);
 	l_5 = LOOP_BEGIN(l_4, l_18);
 	int32_t d_6 = PHI(l_5, d_3, d_15);
diff --git a/tests/019.irt b/tests/019.irt
index 0dc78ac..3646e10 100644
--- a/tests/019.irt
+++ b/tests/019.irt
@@ -10,8 +10,8 @@
 	l_1 = START(l_33);
 	bool d_2 = PARAM(l_1, "cond", 0);
 	int32_t d_3 = PARAM(l_1, "z", 1);
-	bool d_4 = COPY(c_4);
-	bool d_5 = COPY(d_3);
+	int32_t d_4 = COPY(c_4);
+	int32_t d_5 = COPY(d_3);
 	l_6 = END(l_1);
 	l_7 = LOOP_BEGIN(l_6, l_31);
 	int32_t d_8 = PHI(l_7, d_4, d_19);
diff --git a/tests/debug.Windows-x86_64/combo_002.irt b/tests/debug.Windows-x86_64/combo_002.irt
index c25d3a7..37a9a5a 100755
--- a/tests/debug.Windows-x86_64/combo_002.irt
+++ b/tests/debug.Windows-x86_64/combo_002.irt
@@ -15,8 +15,8 @@ Windows-x86_64
 	l_1 = START(l_33);
 	bool d_2 = PARAM(l_1, "cond", 0);
 	int32_t d_3 = PARAM(l_1, "z", 1);
-	bool d_4 = COPY(c_4);
-	bool d_5 = COPY(d_3);
+	int32_t d_4 = COPY(c_4);
+	int32_t d_5 = COPY(d_3);
 	l_6 = END(l_1);
 	l_7 = LOOP_BEGIN(l_6, l_31);
 	int32_t d_8 = PHI(l_7, d_4, d_19);
diff --git a/tests/debug.Windows-x86_64/combo_003.irt b/tests/debug.Windows-x86_64/combo_003.irt
index 5298cb5..1db36bf 100755
--- a/tests/debug.Windows-x86_64/combo_003.irt
+++ b/tests/debug.Windows-x86_64/combo_003.irt
@@ -14,7 +14,7 @@ Windows-x86_64
 	l_1 = START(l_34);
 	bool d_2 = PARAM(l_1, "cond", 0);
 	int32_t d_3 = PARAM(l_1, "z", 1);
-	bool d_4 = COPY(c_4);
+	int32_t d_4 = COPY(c_4);
 	int32_t d_5 = COPY(d_3);
 	l_6 = END(l_1);
 	l_7 = LOOP_BEGIN(l_6, l_31);
diff --git a/tests/debug.aarch64/combo_002.irt b/tests/debug.aarch64/combo_002.irt
index 37c992e..4134f6a 100644
--- a/tests/debug.aarch64/combo_002.irt
+++ b/tests/debug.aarch64/combo_002.irt
@@ -15,8 +15,8 @@ aarch64
 	l_1 = START(l_34);
 	bool d_2 = PARAM(l_1, "cond", 0);
 	int32_t d_3 = PARAM(l_1, "z", 1);
-	bool d_4 = COPY(c_4);
-	bool d_5 = COPY(d_3);
+	int32_t d_4 = COPY(c_4);
+	int32_t d_5 = COPY(d_3);
 	l_6 = END(l_1);
 	l_7 = LOOP_BEGIN(l_6, l_31);
 	int32_t d_8 = PHI(l_7, d_4, d_19);
diff --git a/tests/debug.aarch64/combo_003.irt b/tests/debug.aarch64/combo_003.irt
index 55b1306..876e6f9 100644
--- a/tests/debug.aarch64/combo_003.irt
+++ b/tests/debug.aarch64/combo_003.irt
@@ -14,7 +14,7 @@ aarch64
 	l_1 = START(l_34);
 	bool d_2 = PARAM(l_1, "cond", 0);
 	int32_t d_3 = PARAM(l_1, "z", 1);
-	bool d_4 = COPY(c_4);
+	int32_t d_4 = COPY(c_4);
 	int32_t d_5 = COPY(d_3);
 	l_6 = END(l_1);
 	l_7 = LOOP_BEGIN(l_6, l_31);
diff --git a/tests/debug.x86/combo_002.irt b/tests/debug.x86/combo_002.irt
index 207fcf5..1d8ddc6 100644
--- a/tests/debug.x86/combo_002.irt
+++ b/tests/debug.x86/combo_002.irt
@@ -15,8 +15,8 @@ x86
 	l_1 = START(l_34);
 	bool d_2 = PARAM(l_1, "cond", 0);
 	int32_t d_3 = PARAM(l_1, "z", 1);
-	bool d_4 = COPY(c_4);
-	bool d_5 = COPY(d_3);
+	int32_t d_4 = COPY(c_4);
+	int32_t d_5 = COPY(d_3);
 	l_6 = END(l_1);
 	l_7 = LOOP_BEGIN(l_6, l_31);
 	int32_t d_8 = PHI(l_7, d_4, d_19);
diff --git a/tests/debug.x86/combo_003.irt b/tests/debug.x86/combo_003.irt
index ee48511..9b25c11 100644
--- a/tests/debug.x86/combo_003.irt
+++ b/tests/debug.x86/combo_003.irt
@@ -14,7 +14,7 @@ x86
 	l_1 = START(l_34);
 	bool d_2 = PARAM(l_1, "cond", 0);
 	int32_t d_3 = PARAM(l_1, "z", 1);
-	bool d_4 = COPY(c_4);
+	int32_t d_4 = COPY(c_4);
 	int32_t d_5 = COPY(d_3);
 	l_6 = END(l_1);
 	l_7 = LOOP_BEGIN(l_6, l_31);
diff --git a/tests/debug/combo_002.irt b/tests/debug/combo_002.irt
index 195cc19..36342f6 100644
--- a/tests/debug/combo_002.irt
+++ b/tests/debug/combo_002.irt
@@ -15,8 +15,8 @@ x86_64
 	l_1 = START(l_33);
 	bool d_2 = PARAM(l_1, "cond", 0);
 	int32_t d_3 = PARAM(l_1, "z", 1);
-	bool d_4 = COPY(c_4);
-	bool d_5 = COPY(d_3);
+	int32_t d_4 = COPY(c_4);
+	int32_t d_5 = COPY(d_3);
 	l_6 = END(l_1);
 	l_7 = LOOP_BEGIN(l_6, l_31);
 	int32_t d_8 = PHI(l_7, d_4, d_19);
diff --git a/tests/debug/combo_003.irt b/tests/debug/combo_003.irt
index c1c7791..faab2ee 100644
--- a/tests/debug/combo_003.irt
+++ b/tests/debug/combo_003.irt
@@ -14,7 +14,7 @@ x86_64
 	l_1 = START(l_34);
 	bool d_2 = PARAM(l_1, "cond", 0);
 	int32_t d_3 = PARAM(l_1, "z", 1);
-	bool d_4 = COPY(c_4);
+	int32_t d_4 = COPY(c_4);
 	int32_t d_5 = COPY(d_3);
 	l_6 = END(l_1);
 	l_7 = LOOP_BEGIN(l_6, l_31);