Build: Require GCC 10.1 for std::in_range<>() #1204
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A GCC 9.2 user reported this failure:
In file included from /home/rpm/rpmbuild/BUILD/common/utils/string.cpp:21:
/home/rpm/rpmbuild/BUILD/common/utils/string.hpp: In function 'std::string libdnf5::utils::string::format_epoch(T)':
/home/rpm/rpmbuild/BUILD/common/utils/string.hpp:115:14: error: 'in_range' is not a member of 'std'
115 | if (std::in_range<time_t>(epoch_num)) {
| ^~~~~~~~
The cause is that std::in_range<>() is a C++20 feature added to GCC
in version 10.1.
This patch sets the minimal version in dnf5.spec.
Originally, I also wanted to add a check into a build script to fail
early. std::in_range<>() is supported if the compiler defines
__cpp_lib_integer_comparison_functions >= 202002L feature test macro.
However, checking for it in CMake is very difficult:
target_compile_features() does not recognize this specific feature.
check_cxx_symbol_exists() is unable to retrieve the macro value.
CheckSourceCompiles() requires CMake 3.19 (a year after GCC 10.1).
So I scratched out the idea of adding a check into the build script.
Fixes: rpm-software-management#1167
Merged
via the queue into
rpm-software-management:main
with commit Jan 26, 2024
e5786a8
5 of 9 checks passed
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A GCC 9.2 user reported this failure:
The cause is that std::in_range<>() is a C++20 feature added to GCC in version 10.1.
This patch sets the minimal version in dnf5.spec.
Originally, I also wanted to add a check into a build script to fail early. std::in_range<>() is supported if the compiler defines __cpp_lib_integer_comparison_functions >= 202002L feature test macro.
However, checking for it in CMake is very difficult: target_compile_features() does not recognize this specific feature. check_cxx_symbol_exists() is unable to retrieve the macro value. CheckSourceCompiles() requires CMake 3.19 (a year after GCC 10.1).
So I scratched out the idea of adding a check into the build script.
Fixes: #1167