CMAKE_SYSROOT_COMPILE
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Cmake/docs/3.21/variable/cmake sysroot compile
CMAKE_SYSROOT_COMPILE
New in version 3.9.
Path to pass to the compiler in the --sysroot
flag when compiling source files. This is the same as CMAKE_SYSROOT but is used only for compiling sources and not linking.
This variable may only be set in a toolchain file specified by the CMAKE_TOOLCHAIN_FILE variable.
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Licensed under the BSD 3-clause License.
https://cmake.org/cmake/help/v3.21/variable/CMAKE_SYSROOT_COMPILE.html