commit: 2170307e8e09491f88b0c5f41d42aa096d1b3632
Author: Michał Górny <mgorny <AT> gentoo <DOT> org>
AuthorDate: Fri Oct 7 15:02:28 2022 +0000
Commit: Michał Górny <mgorny <AT> gentoo <DOT> org>
CommitDate: Mon Oct 10 20:52:34 2022 +0000
URL: https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=2170307e
toolchain-funcs.eclass: Add tc-get-cxx-stdlib() to get C++ stdlib
Add a new tc-get-cxx-stdlib() that attempts to get the C++ stdlib
variant used by the current C++ compiler. Currently it supports libc++
and libstdc++ (GCC's stdlib).
Signed-off-by: Michał Górny <mgorny <AT> gentoo.org>
eclass/tests/toolchain-funcs.sh | 22 ++++++++++++++++++++++
eclass/toolchain-funcs.eclass | 36 ++++++++++++++++++++++++++++++++++++
2 files changed, 58 insertions(+)
diff --git a/eclass/tests/toolchain-funcs.sh b/eclass/tests/toolchain-funcs.sh
index 56379b10cded..5a35a44ce018 100755
--- a/eclass/tests/toolchain-funcs.sh
+++ b/eclass/tests/toolchain-funcs.sh
@@ -198,4 +198,26 @@ for compiler in gcc clang not-really-a-compiler; do
fi
done
+if type -P gcc &>/dev/null; then
+ tbegin "tc-get-cxx-stdlib (gcc)"
+ [[ $(CXX=g++ tc-get-cxx-stdlib) == libstdc++ ]]
+ tend $?
+fi
+
+if type -P clang &>/dev/null; then
+ for stdlib in libc++ libstdc++; do
+ if clang++ -stdlib=${stdlib} -x c++ -E -P - &>/dev/null \
+ <<<'#include <ciso646>'
+ then
+ tbegin "tc-get-cxx-stdlib (clang, ${stdlib})"
+ [[ $(CXX=clang++ CXXFLAGS="-stdlib=${stdlib}"
tc-get-cxx-stdlib) == ${stdlib} ]]
+ tend $?
+ fi
+ done
+
+ tbegin "tc-get-cxx-stdlib (clang, invalid)"
+ ! CXX=clang++ CXXFLAGS="-stdlib=invalid" tc-get-cxx-stdlib
+ tend $?
+fi
+
texit
diff --git a/eclass/toolchain-funcs.eclass b/eclass/toolchain-funcs.eclass
index 48bf11606c4a..92494158201e 100644
--- a/eclass/toolchain-funcs.eclass
+++ b/eclass/toolchain-funcs.eclass
@@ -1173,4 +1173,40 @@ gen_usr_ldscript() {
done
}
+# @FUNCTION: tc-get-cxx-stdlib
+# @DESCRIPTION:
+# Attempt to identify the C++ standard library used by the compiler.
+# If the library is identified, the function returns 0 and prints one
+# of the following:
+#
+# - ``libc++`` for ``sys-libs/libcxx``
+# - ``libstdc++`` for ``sys-devel/gcc``'s libstdc++
+#
+# If the library is not recognized, the function returns 1.
+tc-get-cxx-stdlib() {
+ local code='#include <ciso646>
+
+#if defined(_LIBCPP_VERSION)
+ HAVE_LIBCXX
+#elif defined(__GLIBCXX__)
+ HAVE_LIBSTDCPP
+#endif
+'
+ local res=$(
+ $(tc-getCXX) ${CXXFLAGS} ${CPPFLAGS} -x c++ -E -P - \
+ <<<"${code}" 2>/dev/null
+ )
+
+ case ${res} in
+ *HAVE_LIBCXX*)
+ echo libc++;;
+ *HAVE_LIBSTDCPP*)
+ echo libstdc++;;
+ *)
+ return 1;;
+ esac
+
+ return 0
+}
+
fi
