`CMakeDetermineCompilerABI` detects the wrong implicitly linked libraries for G++ when using the Ninja generator, namely omitting `libstdc++` and `libm` whereas the exact same configuration works with the Makefile generator. The reason for this is as follows: Unlike the Makefile generator, Ninja makes heavy usage of GCC response files. For whatever reason GCC's `collect2` link wrapper does not add `libstdc++` and `libm` to its verbose output when using response files. I'm getting on my local machine with an hello world C++ source: * Using `g++ -v @test.rsp -o test` (test.rsp just contains test.o as it does in the case of `CMakeDetermineCompilerABI`) `[...] -L/usr/lib/gcc/x86_64-pc-linux-gnu/6.3.1/../../.. @/tmp/ccBcxraE -lgcc_s -lgcc -lc -lgcc_s -lgcc [...]` * Using `g++ -v test.o -o test`: `[...] -L/usr/lib/gcc/x86_64-pc-linux-gnu/6.3.1/../../.. test.o -lstdc++ -lm -lgcc_s -lgcc -lc -lgcc_s -lgcc [...]` I've omitted the remainder of the output as it's identical. I was able to reproduce this behavior using Scientific Linux 7's default GCC 4.8.5, a self compiled GCC 5.4.0, and the default GCC 6.3 binary from ArchLinux. However, the `collect2` compile wrapper uses `libstdc++` in either case, which can be verified by passing the `-Wl,--verbose` flag. Naturally, the way CMake parses the link flags out of the verbose output in `CMakeParseImplicitLinkInfo` will cause it to not detect `-lstdc++ -lm`. I haven't been able to find any documentation on such behavior in the GCC manual, it just states that the commands read from the @file should be inserted in its place, but the behavior concerning `collect2` or its parameters doesn't seem to be documented. Therefore, I'm not sure whether this qualifies as a bug in GCC (I guess it does?), but given the wide range of affected G++ builds (i.e. all I could try out), I suppose it might be worth it to disable the `rspfile` commands for `CMakeDetermineCompilerABI` and pass the link line directly instead. By doing that, the output generated from the procedure are identical between the Ninja and Makefile generators.