initial commit

1 files changed, 45 insertions, 0 deletions

diff --git a/openssl/bugs/dggccbug.c b/openssl/bugs/dggccbug.c
new file mode 100644
index 0000000..56f5222
--- /dev/null
+++ b/openssl/bugs/dggccbug.c
@@ -0,0 +1,45 @@
+/* NOCW */
+/* dggccbug.c */
+/* bug found by Eric Young (eay@cryptsoft.com) - May 1995 */
+
+#include <stdio.h>
+
+/*
+ * There is a bug in gcc version 2.5.8 (88open OCS/BCS, DG-2.5.8.3, Oct 14
+ * 1994) as shipped with DGUX 5.4R3.10 that can be bypassed by defining
+ * DG_GCC_BUG in my code. The bug manifests itself by the vaule of a pointer
+ * that is used only by reference, not having it's value change when it is
+ * used to check for exiting the loop.  Probably caused by there being 2
+ * copies of the valiable, one in a register and one being an address that is
+ * passed.
+ */
+
+/*-
+ * compare the out put from
+ * gcc dggccbug.c; ./a.out
+ * and
+ * gcc -O dggccbug.c; ./a.out
+ * compile with -DFIXBUG to remove the bug when optimising.
+ */
+
+void inc(a)
+int *a;
+{
+    (*a)++;
+}
+
+main()
+{
+    int p = 0;
+#ifdef FIXBUG
+    int dummy;
+#endif
+
+    while (p < 3) {
+        fprintf(stderr, "%08X\n", p);
+        inc(&p);
+#ifdef FIXBUG
+        dummy += p;
+#endif
+    }
+}