Fix some pointer-arithmetic warnings

This should fix the second part of #59

2 files changed, 3 insertions, 3 deletions

diff --git a/include/fortify-headers.h b/include/fortify-headers.h
index 796fd2d..f7d8af8 100644
--- a/include/fortify-headers.h
+++ b/include/fortify-headers.h
@@ -141,8 +141,8 @@
  * since gcc seems to like to generate code that relies on dst == src */
 #define __fh_overlap(a, len_a, b, len_b) \
         ( \
-                ((a) < (b) && (b) < ((a) + (__fh_size_t)(len_a))) \
-             || ((b) < (a) && (a) < ((b) + (__fh_size_t)(len_b))) \
+                ((char*)(a) < (char*)(b) && (char*)(b) < ((char*)(a) + (__fh_size_t)(len_a))) \
+             || ((char*)(b) < (char*)(a) && (char*)(a) < ((char*)(b) + (__fh_size_t)(len_b))) \
         )
 
 /*
diff --git a/tests/Makefile b/tests/Makefile
index 32b17b0..d6f5b5d 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -1,4 +1,4 @@
-CFLAGS+=-I../include/ -D_FORTIFY_SOURCE=3 -static -O2 -DPEDANTIC_CHECKS -Wno-format
+CFLAGS+=-I../include/ -D_FORTIFY_SOURCE=3 -static -O2 -DPEDANTIC_CHECKS -Wno-format -Werror=pointer-arith
 
 COMPTIME_TARGETS= \
         test_memcpy_overwrite_under  \