Automatically extract version information
from the zstd.h file. Use naming of variables
consisent with modern cmake and https://semver.org/
(Semantic Versioning 2.0.0, MAJOR, MINOR, PATCH)
Modern versions of cmake provide consistent
paradigms for configuring project external
interface values.
This set of changes provide a back port of
some of cmake 3+ paradigms back to cmake 2.8.9.
Set and allow use of the current cmake policies
for newer versions of cmake when available to
allow for modern compiler features to be
utilized when available.
NOTE: The intent is that future modifications to
cmake will enable (conditional on cmake version support)
the ability to support modern linkage, and target
export mechanisms. Those future changes will
make incorporating zstd into other packages
much easier.
This patch also allows the more rigourous error
checking of commmon cmake errors to be preformed
by cmake (i.e. more stringent syntax checking and
create errors for common hard to find misuses of
cmake variables).
This patch also provides support for modern
compiler support options by cmake (like
enabling interprocedural optimization
if link time optimizations are known to be supported
by the compiler envirionment. IPO can be supported
by setting the CMAKE_INTERPROCEDURAL_OPTIMIZATION variable
for newer versions of cmake.
due to bad support of inode identifiers.
On Visual, option is limited to same file name,
which is imperfect, but way better than disabling the feature entirely.
It's enough to pass associated tests.
On Windows, the equivalent of `/dev/null` is `NUL`.
When tests are run under msys2/minGW,
the environment identifies itself as Windows,
hence the script uses `NUL` instead of `/dev/null`
but the environment will consider `NUL` to be a regular file name.
Consequently, `NUL` will be overwritten during tests,
triggering an error.
This patch uses flag `-f` to force such overwrite
passing the test.
When compiling without c++ enabled, some variables are not present.
This is a check enforced in recent Cmake versions.
CMake Error at CMakeModules/AddZstdCompilationFlags.cmake:54 (list):
list sub-command REMOVE_DUPLICATES requires list to be present.
Call Stack (most recent call first):
CMakeLists.txt:53 (ADD_ZSTD_COMPILATION_FLAGS)
The CMAKE_BUILD_TYPE variable is a CACHE variable
and should be set in a way that persists and is
documented in the CACHE. Also set the default
values for the gui to ease selection of types.
These changes provide better support for GUI
configurators that support cmake.
It's incorrect to mix targets `all` and `check` with directive -j.
They will be build in parallel
and resulting artifacts will fight each other
with different sets of build options (such as DEBUGLEVEL).
Ancient versions of CMake required else(), endif(), and similar block
termination commands to have arguments matching the command starting the block.
This is no longer the preferred style.
as suggested in #1441.
generally U32 and unsigned are the same thing,
except when they are not ...
case : 32-bit compilation for MIPS (uint32_t == unsigned long)
A vast majority of transformation consists in transforming U32 into unsigned.
In rare cases, it's the other way around (typically for internal code, such as seeds).
Among a few issues this patches solves :
- some parameters were declared with type `unsigned` in *.h,
but with type `U32` in their implementation *.c .
- some parameters have type unsigned*,
but the caller user a pointer to U32 instead.
These fixes are useful.
However, the bulk of changes is about %u formating,
which requires unsigned type,
but generally receives U32 values instead,
often just for brevity (U32 is shorter than unsigned).
These changes are generally minor, or even annoying.
As a consequence, the amount of code changed is larger than I would expect for such a patch.
Testing is also a pain :
it requires manually modifying `mem.h`,
in order to lie about `U32`
and force it to be an `unsigned long` typically.
On a 64-bit system, this will break the equivalence unsigned == U32.
Unfortunately, it will also break a few static_assert(), controlling structure sizes.
So it also requires modifying `debug.h` to make `static_assert()` a noop.
And then reverting these changes.
So it's inconvenient, and as a consequence,
this property is currently not checked during CI tests.
Therefore, these problems can emerge again in the future.
I wonder if it is worth ensuring proper distinction of U32 != unsigned in CI tests.
It's another restriction for coding, adding more frustration during merge tests,
since most platforms don't need this distinction (hence contributor will not see it),
and while this can matter in theory, the number of platforms impacted seems minimal.
Thoughts ?
Yann Collet
Erik Webb
Yann Collet
Hans Johnson
Dmitry V. Levin
Lzu Tao
Nick Terrell
Nick Terrell