diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 63b1981daae..4175e023251 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2008-08-27  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>
+
+	PR 37217
+	* c-common.c (convesion_warning): Check for null operands.
+
 2008-08-27  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>
 
 	PR c/31673
diff --git a/gcc/c-common.c b/gcc/c-common.c
index d06c96940f4..e0a0829ec58 100644
--- a/gcc/c-common.c
+++ b/gcc/c-common.c
@@ -1568,7 +1568,7 @@ conversion_warning (tree type, tree expr)
   for (i = 0; i < expr_num_operands; i++)
     {
       tree op = TREE_OPERAND (expr, i);
-      if (DECL_P (op) && DECL_ARTIFICIAL (op))
+      if (op && DECL_P (op) && DECL_ARTIFICIAL (op))
 	return;
     }
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index d5d73d74a0c..707ccb7431d 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2008-08-27  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>
+
+	PR 37217
+	* gcc.dg/pr37217.c: New.
+
 2008-08-27  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>
 
 	PR c/31673
diff --git a/gcc/testsuite/gcc.dg/pr37217.c b/gcc/testsuite/gcc.dg/pr37217.c
new file mode 100644
index 00000000000..989eda2cd88
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr37217.c
@@ -0,0 +1,10 @@
+/* PR 37217 ICE with -Wconversion */
+/* { dg-do compile } */
+/* { dg-options "-Wconversion" } */
+typedef struct Tcl_ResolvedVarInfo {
+  char *re_guts;
+} regex_t;
+void TclReComp(regex_t *re)
+{
+  if (re->re_guts == ((void *)0)) ;
+}