diff --git a/acb_mat.h b/acb_mat.h
index 2ec77512..52939535 100644
--- a/acb_mat.h
+++ b/acb_mat.h
@@ -66,6 +66,16 @@ acb_mat_swap(acb_mat_t mat1, acb_mat_t mat2)
     *mat2 = t;
 }
 
+ACB_MAT_INLINE void
+acb_mat_swap_entrywise(acb_mat_t mat1, acb_mat_t mat2)
+{
+    slong i, j;
+
+    for (i = 0; i < acb_mat_nrows(mat1); i++)
+        for (j = 0; j < acb_mat_ncols(mat1); j++)
+            acb_swap(acb_mat_entry(mat2, i, j), acb_mat_entry(mat1, i, j));
+}
+
 /* Window matrices */
 
 void acb_mat_window_init(acb_mat_t window, const acb_mat_t mat, slong r1, slong c1, slong r2, slong c2);
diff --git a/acb_mat/approx_mul.c b/acb_mat/approx_mul.c
index 078dd4e1..d84294d4 100644
--- a/acb_mat/approx_mul.c
+++ b/acb_mat/approx_mul.c
@@ -38,7 +38,7 @@ acb_mat_approx_mul_classical(acb_mat_t C, const acb_mat_t A, const acb_mat_t B,
         acb_mat_t T;
         acb_mat_init(T, ar, bc);
         acb_mat_approx_mul_classical(T, A, B, prec);
-        acb_mat_swap(T, C);
+        acb_mat_swap_entrywise(T, C);
         acb_mat_clear(T);
         return;
     }
diff --git a/acb_mat/mul_classical.c b/acb_mat/mul_classical.c
index 23021456..40bfa1ef 100644
--- a/acb_mat/mul_classical.c
+++ b/acb_mat/mul_classical.c
@@ -45,7 +45,7 @@ acb_mat_mul_classical(acb_mat_t C, const acb_mat_t A, const acb_mat_t B, slong p
         acb_mat_t T;
         acb_mat_init(T, ar, bc);
         acb_mat_mul_classical(T, A, B, prec);
-        acb_mat_swap(T, C);
+        acb_mat_swap_entrywise(T, C);
         acb_mat_clear(T);
         return;
     }
diff --git a/acb_mat/mul_threaded.c b/acb_mat/mul_threaded.c
index f6aac610..289137d9 100644
--- a/acb_mat/mul_threaded.c
+++ b/acb_mat/mul_threaded.c
@@ -87,7 +87,7 @@ acb_mat_mul_threaded(acb_mat_t C, const acb_mat_t A, const acb_mat_t B, slong pr
         acb_mat_t T;
         acb_mat_init(T, ar, bc);
         acb_mat_mul_threaded(T, A, B, prec);
-        acb_mat_swap(T, C);
+        acb_mat_swap_entrywise(T, C);
         acb_mat_clear(T);
         return;
     }
diff --git a/arb_mat.h b/arb_mat.h
index b28652a9..f8c2788b 100644
--- a/arb_mat.h
+++ b/arb_mat.h
@@ -64,6 +64,16 @@ arb_mat_swap(arb_mat_t mat1, arb_mat_t mat2)
     *mat2 = t;
 }
 
+ARB_MAT_INLINE void
+arb_mat_swap_entrywise(arb_mat_t mat1, arb_mat_t mat2)
+{
+    slong i, j;
+
+    for (i = 0; i < arb_mat_nrows(mat1); i++)
+        for (j = 0; j < arb_mat_ncols(mat1); j++)
+            arb_swap(arb_mat_entry(mat2, i, j), arb_mat_entry(mat1, i, j));
+}
+
 /* Window matrices */
 
 void arb_mat_window_init(arb_mat_t window, const arb_mat_t mat, slong r1, slong c1, slong r2, slong c2);
diff --git a/arb_mat/approx_mul.c b/arb_mat/approx_mul.c
index 0ac9cb38..15aff9cd 100644
--- a/arb_mat/approx_mul.c
+++ b/arb_mat/approx_mul.c
@@ -31,7 +31,7 @@ arb_mat_approx_mul_classical(arb_mat_t C, const arb_mat_t A, const arb_mat_t B,
         arb_mat_t T;
         arb_mat_init(T, ar, bc);
         arb_mat_approx_mul_classical(T, A, B, prec);
-        arb_mat_swap(T, C);
+        arb_mat_swap_entrywise(T, C);
         arb_mat_clear(T);
         return;
     }
diff --git a/arb_mat/mul_block.c b/arb_mat/mul_block.c
index b63e2d61..3f91b723 100644
--- a/arb_mat/mul_block.c
+++ b/arb_mat/mul_block.c
@@ -238,7 +238,7 @@ arb_mat_mul_block(arb_mat_t C, const arb_mat_t A, const arb_mat_t B, slong prec)
         arb_mat_t T;
         arb_mat_init(T, M, P);
         arb_mat_mul_block(T, A, B, prec);
-        arb_mat_swap(T, C);
+        arb_mat_swap_entrywise(T, C);
         arb_mat_clear(T);
         return;
     }
diff --git a/arb_mat/mul_classical.c b/arb_mat/mul_classical.c
index 82f301bd..47eeb197 100644
--- a/arb_mat/mul_classical.c
+++ b/arb_mat/mul_classical.c
@@ -45,7 +45,7 @@ arb_mat_mul_classical(arb_mat_t C, const arb_mat_t A, const arb_mat_t B, slong p
         arb_mat_t T;
         arb_mat_init(T, ar, bc);
         arb_mat_mul_classical(T, A, B, prec);
-        arb_mat_swap(T, C);
+        arb_mat_swap_entrywise(T, C);
         arb_mat_clear(T);
         return;
     }
diff --git a/arb_mat/mul_threaded.c b/arb_mat/mul_threaded.c
index 30ea5923..9d82c1b4 100644
--- a/arb_mat/mul_threaded.c
+++ b/arb_mat/mul_threaded.c
@@ -87,7 +87,7 @@ arb_mat_mul_threaded(arb_mat_t C, const arb_mat_t A, const arb_mat_t B, slong pr
         arb_mat_t T;
         arb_mat_init(T, ar, bc);
         arb_mat_mul_threaded(T, A, B, prec);
-        arb_mat_swap(T, C);
+        arb_mat_swap_entrywise(T, C);
         arb_mat_clear(T);
         return;
     }
diff --git a/stBhzi4B b/stBhzi4B
new file mode 100644
index 00000000..e69de29b