installation.

a compile time print was added warning in case of 128bit ctr_drbg keys.
This was don't to avoid an actual warning in these cases
(making build with warnings as errors possible).
Additional warnings on the Changelog/headers were set to use the same phrasing
phrasing was approved by Gilles and Janos.

Remove unnecessary defines from the test.
Test by defining TEST_CPP using makefiles or cmake.

In case of any problems with the 'extern "C"' directives,
building the executable will fail

Fix IAR compiler warnings

Two warnings have been fixed:
1. code 'if( len <= 0xFFFFFFFF )' gave warning 'pointless integer comparison'.
   This was fixed by wraping the condition in '#if SIZE_MAX > 0xFFFFFFFF'.
2. code 'diff |= A[i] ^ B[i];' gave warning 'the order of volatile accesses is undefined in'.
   This was fixed by read the volatile data in temporary variables before the computation.

Explain IAR warning on volatile access

Consistent use of CMAKE_C_COMPILER_ID

Change the value of `-fno-sanitize-recover` from `undefined,integer` to `all`

Create extra symbolic links with CMake so that SSL testing (ssl-opt.sh
and compat.sh) works in out-of-tree builds.

When the Doxywizzard GUI is used and the doxyfile is loaded, the
workind directory for doxygen is set to the location of the doxyfile.
However the Make and CMake build systems expect doxygen to be ran
from the top level directory.
This commit unifies the build system and the Doxywizzard GUI so that
all of them expect doxygen to be executed in the doxygen directory.

Support only new CLang version by enabling only
`-fno-sanitize-recover=undefined,integer`

Fix typo and use new check for clang>3.5m according to azim's comments

Check CLANG version, and according to the version,
set the correct paramters. fix for #1072

That way, the project integrate more nicely when used as a cmake sub-project.

Compiler warnings were being configured twice and not suppressed on the
test suites with Microsoft Visual Studio.

Compiler warnings were being configured twice and not suppressed on the
test suites with Microsoft Visual Studio.

Allow mbed TLS to be build in a subdirectory. Also add a test in
all.sh

If the option MBEDTLS_TEST_NULL_ENTROPY is enabled, the cmake generated
makefile will generate an error unless a UNSAFE_BUILD switch is also enabled.

Equally, a similar warning will always be generated if the Makefile is built,
and another warning is generated on every compilation of entropy.c.

This is to ensure the user is aware of what they're doing when they enable the
null entropy option.

Removed SSLv3 from the default tests in compat.sh, and adapted the test
cases in all.sh to include an additional SSLv3 regression test suite.

Change the default settings for SSL and modify the tests accordingly.

Removed SSLv3 from the default tests in compat.sh, and adapted the test
cases in all.sh to include an additional SSLv3 regression test suite.

Change the default settings for SSL and modify the tests accordingly.

This partially reverts 1989caf7 (only the changes to Makefile and
CMakeLists, the addition to scripts/config.pl is kept).

Modifying config.h in the apidoc target creates a race condition with

    make -j4 all apidoc

where some parts of the library, tests or programs could be built with the
wrong config.h, resulting in all kinds of (semi-random) errors. Recent
versions of CMake mitigate this by adding a .NOTPARALLEL target to the
generated Makefile, but people would still get errors with older CMake
versions that are still in use (eg in RHEL 5), and with plain make.

An additional issue is that, by failing to use cp -p, the apidoc target was
updating the timestamp on config.h, which seems to cause further build issues.

Let's get back to the previous, safe, situation. The improved apidoc building
will be resurrected in a script in the next commit.

fixes #390
fixes #391

Otherwise we get warnings that some documentation items don't have
corresponding #define, and more importantly the corresponding snippets are not
included in the output.

For that we need a modified version of the "full" argument for config.pl.

Also, the new CMakeLists.txt target only works on Unix (which was already the
case of the Makefile target). Hopefully this is not an issue as people are
unlikely to need that target on Windows.

Before that, we get useless warnings about local variables shadowing extern
functions, which means we can't have a local variable called index when we
include string.h.

https://lkml.org/lkml/2006/11/28/239
https://gcc.gnu.org/gcc-4.8/changes.html

Checked that it is supported by gcc 4.2.1 (FreeBSD 9).

fixes #240

closes #235

Previously testing was enabled only if GCC || Clang, and I though this was a
"proxy" for the likelihood of Perl being available. Apparently it was not just
that, since MSVC gives me a lot of errors when trying to build tests.

Let's fix them later, and disable for now.