Projects use `try_compile` to check if they will be able to compile some
particular source code. When a language standard variable like
`CMAKE_CXX_STANDARD` is set, then the project intends to compile source
code using a compiler mode for that standard. Therefore it makes sense
for `try_compile` to use that standard in the test project too.
Unfortunately this was not done when support for the
`CMAKE_CXX_STANDARD` variable was first implemented. Add a policy to
introduce the improved behavior in a compatible way.
Closes: #16456
Give `try_compile` callers a way to control the `CXX_STANDARD`,
`CXX_STANDARD_REQUIRED`, and `CXX_EXTENSIONS` properties of the
generated test target (or the `C` equivalents) in order to compile a
test source for a particular language standard.
Issue: #16456
Failing to generate the build system of the test project is a failure to
compute the result of the test compilation, and so must be treated as
any other CMake Error and stop processing.
97c1e569 Help: Add release note for C++ 17 support
85c8e652 Features: Activate C++ 17 support for AppleClang 6.1+
8084f7a6 Features: Activate C++ 17 support for Clang 3.5+
24e29d41 Features: Activate C++ 17 support for GNU 5.1+
ae1a6815 Features: Add infrastructure for C++ 17 language standard
684e4d20 Features: Make feature recording conditions more consistent
Logic added by commit 1e4bb358 (Add generator expression support to
per-source COMPILE_FLAGS, 2016-10-25) accidentally frees memory before
finishing with it. Revise the logic to hold the memory long enough.
Add these (currently unused) tables in preparation for `.csproj`
generation support. Populate the tables for every version with a set of
initial values that work well for me with VS 12 and VS 14. Later we may
need to generate them more thoroughly from MSBuild `.xml` files.
Generalize some internal infrastructure to prepare for generating
either `.vcxproj` or `.csproj` files.
- Add member string for project file extension
- Add member enum for project type
- Add member flag for in-source build
- Add member flag for managed build
- Rename PathToVcxproj to PathToProjectFile