re PR sanitizer/81902 (new -fsanitize=pointer-overflow option undocumented)

	PR sanitizer/81902
	* doc/invoke.texi: Document -fsanitize=pointer-overflow.

From-SVN: r251596

gcc/ChangeLog

 2017-09-01  Jakub Jelinek  <jakub@redhat.com>
 
+	PR sanitizer/81902
+	* doc/invoke.texi: Document -fsanitize=pointer-overflow.
+
 	PR sanitizer/81923
 	* asan.c (create_odr_indicator): Strip name encoding from assembler
 	name before appending it after __odr_asan_.

gcc/doc/invoke.texi

@@ -11074,6 +11074,12 @@ This option enables instrumentation of C++ member function calls, member
 accesses and some conversions between pointers to base and derived classes,
 to verify the referenced object has the correct dynamic type.
 
+@item -fsanitize=pointer-overflow
+@opindex fsanitize=pointer-overflow
+
+This option enables instrumentation of pointer arithmetics.  If the pointer
+arithmetics overflows, a run-time error is issued.
+
 @end table
 
 While @option{-ftrapv} causes traps for signed overflows to be emitted,