Change the default value of `CMAKE_AUTOMOC_PATH_PREFIX` to `OFF` to
restore compatibility with behavior of CMake 3.15 and below.
C++ source files that are generated by Qt's meta object compiler (moc)
include the header file that was passed as input argument to moc. This
is usually a path relative to the source directory, for example
#include "../../source/dir/myobject.h"
That is problematic for reproducible builds as described in #18815.
To cope with that, the target property AUTOMOC_PATH_PREFIX was
introduced in CMake 3.16 by commit d018d27c10 (Autogen: Add moc path
prefix generation (AUTOMOC_PATH_PREFIX), 2019-09-13, v3.16.0-rc1~94^2~4).
The property is default-initialized from the variable
`CMAKE_AUTOMOC_PATH_PREFIX`, which defaults to `ON`.
If this property is ON, and myobject.h is located in an include
directory of the target, moc-generated C++ files include the file
without the "path prefix":
#include "myobject.h"
This behavior, however, can break projects that have equally named
header files in different include directories. As "not breaking
existing projects" trumps "have reproducible builds by default" we
change the default of `CMAKE_AUTOMOC_PATH_PREFIX` to `OFF`.
Also, it is now possible to pass `-DCMAKE_AUTOMOC_PATH_PREFIX=ON` on the
CMake command line. Before, it was overridden in `CMakeGenericSystem`.
Fixes: #20598
Issue: #18815
When using Qt 5.15.0 or above together with Ninja, check that touching
a source file of a dependency does not needlessly re-run AUTOMOC for
the dependee target.
The AutoMoc timestamp creating custom command explicitly depended
on all dependencies of the origin target (associated to the AutoGen
target).
When an origin target depended on a shared library 'libfoo.so',
if it was re-linked, the AutoMoc custom command would touch its
output timestamp file, and thus cause needless rebuilding of sources,
despite the shared library not having any influence on the AutoMoc
generated files.
Introduce a new '<target>_autogen_timestamp_deps' utility target,
which will serve as an 'order-only' dependency for the custom command.
This will prevent needless rebuilding, because touching 'libfoo.so'
will not cause the custom command to be re-executed.
The new AutoMoc dependency tree looks like:
'_autogen_timestamp_deps (serves as order-only dep)'
<- '<target_autogen>/timestamp' file ( + moc deps file)
<- '<target>_autogen' target.
Fixes: #21020
In commit 99ed39b011 (Ninja Multi-Config: Make link response files
per-config, 2020-07-15, v3.17.4~3^2), we added the target directory to
the response file under the mistaken assumption that two different
targets with the same name could be in different directories. However,
this causes the path to the response file to be too long to fit on a
command line. Take the path back out, while leaving in the per-config
split.
Fixes: #21050
Refactoring in commit 889a7146ff (GoogleTestAddTests: Refactor into
callable method, 2020-03-16, v3.18.0-rc1~450^2~3) accidentally
parsed `TEST_EXECUTOR` as a single-value argument instead of a list.
Fix logic added by commit fc5afbe970 (FindCURL: support COMPONENTS to
check features, 2018-11-28, v3.14.0-rc1~287^2~2).
When searching for particular components and `curl-config` reports one of
the components being searched for first in the list, `find_package` fails.
This is due to the check that treats non-zero index in the list as success
and zero index as failure, while documentation on `list(FIND)` states that
failure to find an element results in return value of -1 (not 0). I'm
hitting this when building cURL with support for HTTP and HTTPS protocols
only, and then trying to `find_package(CURL COMPONENTS HTTP HTTPS)`.
I'm using `if(NOT x EQUAL -1)` check form as it appears to be the most used
throughout the modules.
While fixing this issue I've looked through all the uses of `list(FIND)` in
other modules but wasn't able to find improper use except here.
Revert commit f84af8e270 (add_test: Allow special characters in test
name, 2020-05-16, v3.18.0-rc1~142^2). Unfortunately the fix breaks
projects that were working around the limitation with manual escaping.
The fix can be re-introduced with a policy in a future version.
Also add a 3.18.1 release note explaining the change.
Fixes: #21017, #20965
Issue: #19391
Since commit 8cc384f629 (Compilers: Add paths from -print-sysroot to
system prefix path, 2020-03-25, v3.18.0-rc1~337^2) we prepend the
compiler's sysroot to `CMAKE_SYSTEM_PREFIX_PATH`. This does not
make sense when the prefix is just `/`, such as on Ubuntu 16.04's
system compiler.
Fixes: #21019
796466284b bootstrap: Fix support for Intel compiler with modern GNU system compiler
Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !5057
The optimization from commit 627fc5b44f (ExternalProject: Avoid
unnecessary checkout on clone, 2019-07-29, v3.16.0-rc1~325^2) triggers a
bug in the Git 2.20.x series that is not in older or newer versions.
Drop the optimization for that specific range of Git versions.
Fixes: #21009
On systems with older GNU system compilers, the Intel C++ compiler does
not define `__cplusplus` to any version newer than C++11. This
prevented `bootstrap` from detecting that a given C++ standard flag has
enabled C++17 mode in the compiler. In commit 033a4b12a5 (bootstrap:
Extend C++17 check for our cast functions, 2019-12-14,
v3.17.0-rc1~291^2) we added a preprocessor condition to attempt to
detect C++17 mode in the Intel compiler on such systems by looking
for `__cpp_if_constexpr`. However, on systems with a modern GNU
system compiler, that definition is available even in C++11 mode.
Switch to using `__cpp_deduction_guides` to detect C++17 mode for the
Intel C++ compiler. That seems to be defined exclusively in C++17 mode
regardless of the version of the system compiler.
Fixes: #21013
Xcode 12 beta 3 now warns about using the legacy build system.
Since generation of the build system is CMake's responsibility,
the warning is not relevant to our users. Suppress it.
Issue: #18088
Since commit 3b547e2e4b (VS: Simplify logic adding source file C/C++
language flag to MSVC, 2020-05-15, v3.18.0-rc1~139^2~1) we only add a
per-source language selection flag when the source file extension does
not match the compiler's default. This approach breaks when a project
adds a target-wide `-TP` flag.
Although such projects likely did not work with non-VS generators, we
did support them before in Visual Studio generators. Add a special case
to tolerate such flags again.
Fixes: #21005
In commit d7679f6427 (QCMakeCacheView: use non-deprecated List and Set
constructions, 2020-06-10, v3.18.0-rc2~13^2) the conversion of the
`this->properties()` value to QSet is incorrect for Qt 5.14+. The
problem is that `this->properties()` returns by value, so the range
`this->properties().begin(), this->properties().end()` provides
iterators to two different instances. Use an intermediate temporary
copy of the value to get a consistent iterator range.
Fixes: #20981
Brad King