1 files changed, 100 insertions, 0 deletions
diff --git a/gcc/testsuite/g++.dg/init/array52.C b/gcc/testsuite/g++.dg/init/array52.C
new file mode 100644
index 00000000000..e7b4cb394ad
--- /dev/null
+++ b/gcc/testsuite/g++.dg/init/array52.C
@@ -0,0 +1,100 @@
+// PR c++/89980 - pointer initialization with empty string folded to zero
+// { dg-do compile }
+// { dg-options "-O2 -Wall -fdump-tree-optimized" }
+
+#if __cplusplus >= 201103L
+
+#define SA(e) static_assert (e, #e)
+
+static constexpr const char* const ca1[2] = { "" };
+
+void fca1 (void)
+{
+  SA (ca1[0] && ca1[0][0] == 0 && ca1[1] == 0);
+}
+
+static constexpr const char* const ca2[][2] =
+{
+  { }, { 0 }, { 0, 0 }, { "" }, { "", "" }, { "", 0 }, { 0, "" }
+};
+
+void fca2 (void)
+{
+  SA (ca2[0][0] == 0 && ca2[0][1] == 0);
+  SA (ca2[1][0] == 0 && ca2[1][1] == 0);
+  SA (ca2[2][0] == 0 && ca2[2][1] == 0);
+
+  SA (ca2[3][0] && ca2[3][0][0] == 0 && ca2[3][1] == 0);
+  SA (ca2[4][0] && ca2[4][0][0] == 0 && ca2[4][1] && ca2[4][1][0] == 0);
+  SA (ca2[5][0] && ca2[5][0][0] == 0 && ca2[5][1] == 0);
+  SA (ca2[6][0] == 0 && ca2[6][1] && ca2[6][1][0] == 0);
+}
+
+struct A
+{
+  const char *p;
+  char a[2];
+};
+
+static constexpr A ca3[] =
+{
+  {  }, { 0 }, { 0, "" }, { "" }, { "", "" }
+};
+
+void fca3 (void)
+{
+  SA (ca3[0].p == 0 && ca3[0].a[0] == 0 && ca3[0].a[1] == 0);
+  SA (ca3[1].p == 0 && ca3[1].a[0] == 0 && ca3[1].a[1] == 0);
+  SA (ca3[2].p == 0 && ca3[2].a[0] == 0 && ca3[2].a[1] == 0);
+  SA (ca3[3].p && ca3[3].p[0] == 0 && ca3[3].a[0] == 0 && ca3[3].a[1] == 0);
+  SA (ca3[4].p && ca3[4].p[0] == 0 && ca3[4].a[0] == 0 && ca3[4].a[1] == 0);
+}
+
+#endif   // C++ 11 and above
+
+
+#define A(e) ((e) ? (void)0 : __builtin_abort ())
+
+static const char* const a1[2] = { "" };
+
+void fa1 (void)
+{
+  A (a1[0] && a1[0][0] == 0 && a1[1] == 0);
+}
+
+static const char* const a2[][2] =
+{
+  { }, { 0 }, { 0, 0 }, { "" }, { "", "" }, { "", 0 }, { 0, "" }
+};
+
+void fa2 (void)
+{
+  A (a2[0][0] == 0 && a2[0][1] == 0);
+  A (a2[1][0] == 0 && a2[1][1] == 0);
+  A (a2[2][0] == 0 && a2[2][1] == 0);
+
+  A (a2[3][0] && a2[3][0][0] == 0 && a2[3][1] == 0);
+  A (a2[4][0] && a2[4][0][0] == 0 && a2[4][1] && a2[4][1][0] == 0);
+  A (a2[5][0] && a2[5][0][0] == 0 && a2[5][1] == 0);
+  A (a2[6][0] == 0 && a2[6][1] && a2[6][1][0] == 0);
+}
+
+struct B
+{
+  const char *p;
+  char a[2];
+};
+
+static const B a3[] =
+{
+  {  }, { 0 }, { 0, "" }, { "" }, { "", "" }
+};
+
+void fa3 (void)
+{
+  A (a3[0].p == 0 && a3[0].a[0] == 0 && a3[0].a[1] == 0);
+  A (a3[1].p == 0 && a3[1].a[0] == 0 && a3[1].a[1] == 0);
+  A (a3[2].p == 0 && a3[2].a[0] == 0 && a3[2].a[1] == 0);
+  A (a3[3].p && a3[3].p[0] == 0 && a3[3].a[0] == 0 && a3[3].a[1] == 0);
+  A (a3[4].p && a3[4].p[0] == 0 && a3[4].a[0] == 0 && a3[4].a[1] == 0);
+}