3 tests failing with gcc 5.3 (-O3 and also -O2)

[anthraxx]

Hi, me again 😄

I have noticed that the current git HEAD has 3 failing tests (the latest release works fine and all tests are passing).
This happens with both, -O2 and -O3 with gcc 5.3.0.
The failing tests are:

[==========] Running 4 test(s).
[ RUN      ] test_last_page_map
ERROR: Invalid memory write (UC_ERR_WRITE_UNMAPPED)
test_mem_high.c:47: error: Failure!

[  FAILED  ] test_last_page_map
[ RUN      ] test_high_address_reads
ERROR: Invalid memory read (UC_ERR_READ_UNMAPPED)
test_mem_high.c:83: error: Failure!

[  FAILED  ] test_high_address_reads
[ RUN      ] test_high_address_read_values
ERROR: Invalid memory write (UC_ERR_WRITE_UNMAPPED)
test_mem_high.c:100: error: Failure!

[  FAILED  ] test_high_address_read_values
[ RUN      ] test_nullptr_deref_wrong_perms
[       OK ] test_nullptr_deref_wrong_perms
[==========] 4 test(s) run.
[  PASSED  ] 1 test(s).
[  FAILED  ] 3 test(s), listed below:
[  FAILED  ] test_last_page_map
[  FAILED  ] test_high_address_reads
[  FAILED  ] test_high_address_read_values

 3 FAILED TEST(S)