diff --git a/gcc/ree.cc b/gcc/ree.cc
index 98bd80efd7b..413aec7c8eb 100644
--- a/gcc/ree.cc
+++ b/gcc/ree.cc
@@ -875,7 +875,8 @@ combine_reaching_defs (ext_cand *cand, const_rtx set_pat, ext_state *state)
 
 	  for (df_link *use = uses; use; use = use->next)
 	    if (paradoxical_subreg_p (GET_MODE (*DF_REF_LOC (use->ref)),
-				      GET_MODE (SET_DEST (*dest_sub_rtx))))
+				      GET_MODE (SET_DEST (*dest_sub_rtx)))
+		&& !DEBUG_INSN_P (DF_REF_INSN (use->ref)))
 	      return false;
 	}
 
@@ -963,7 +964,8 @@ combine_reaching_defs (ext_cand *cand, const_rtx set_pat, ext_state *state)
 	      rtx dest2 = SET_DEST (*dest_sub_rtx2);
 	      for (use = uses; use; use = use->next)
 		if (paradoxical_subreg_p (GET_MODE (*DF_REF_LOC (use->ref)),
-					  GET_MODE (dest2)))
+					  GET_MODE (dest2))
+		    && !DEBUG_INSN_P (DF_REF_INSN (use->ref)))
 		  break;
 	      if (use)
 		break;
diff --git a/gcc/testsuite/gcc.dg/pr108573.c b/gcc/testsuite/gcc.dg/pr108573.c
new file mode 100644
index 00000000000..5dd18043b2b
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr108573.c
@@ -0,0 +1,18 @@
+/* PR debug/108573 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fcompare-debug" } */
+
+unsigned g;
+
+int bar (void);
+int baz (int);
+
+void
+foo (unsigned short s, long l)
+{
+  unsigned u = bar ();
+  s &= __builtin_add_overflow_p (0, u, 0);
+  s %= g;
+  s -= l >> s;
+  baz (s);
+}