clang++ doesn't compile cmath in macOS Catalina - macos

Question

I have a simple C++ program that imports cmath.
#include <cmath>
int main() {
return 0;
}
I'm trying to compile it using the following command.
clang++ -o test main.cpp -std=c++14
But, I get the following errors
In file included from main.cpp:2:
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:317:9: error:
no member named 'signbit' in the global namespace
using ::signbit;
~~^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:318:9: error:
no member named 'fpclassify' in the global namespace
using ::fpclassify;
~~^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:319:9: error:
no member named 'isfinite' in the global namespace; did you mean 'finite'?
using ::isfinite;
~~^
/usr/local/include/math.h:749:12: note: 'finite' declared here
extern int finite(double)
^
In file included from main.cpp:2:
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:320:9: error:
no member named 'isinf' in the global namespace
using ::isinf;
~~^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:321:9: error:
no member named 'isnan' in the global namespace
using ::isnan;
~~^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:322:9: error:
no member named 'isnormal' in the global namespace
using ::isnormal;
~~^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:323:9: error:
no member named 'isgreater' in the global namespace
using ::isgreater;
~~^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:324:9: error:
no member named 'isgreaterequal' in the global namespace
using ::isgreaterequal;
~~^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:325:9: error:
no member named 'isless' in the global namespace
using ::isless;
~~^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:326:9: error:
no member named 'islessequal' in the global namespace
using ::islessequal;
~~^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:327:9: error:
no member named 'islessgreater' in the global namespace
using ::islessgreater;
~~^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:328:9: error:
no member named 'isunordered' in the global namespace
using ::isunordered;
~~^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:329:9: error:
no member named 'isunordered' in the global namespace
using ::isunordered;
~~^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:335:9: error:
no member named 'abs' in the global namespace; did you mean 'fabs'?
using ::abs;
~~^
/usr/local/include/math.h:417:15: note: 'fabs' declared here
extern double fabs(double);
^
In file included from main.cpp:2:
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:640:26: error:
no template named 'numeric_limits'
bool _FloatBigger = (numeric_limits<_FloatT>::digits > numeric_limits<_IntT>::digits),
^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:640:60: error:
no template named 'numeric_limits'
bool _FloatBigger = (numeric_limits<_FloatT>::digits > numeric_limits<_IntT>::digits),
^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:641:18: error:
no template named 'numeric_limits'
int _Bits = (numeric_limits<_IntT>::digits - numeric_limits<_FloatT>::digits)>
^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:641:50: error:
no template named 'numeric_limits'
int _Bits = (numeric_limits<_IntT>::digits - numeric_limits<_FloatT>::digits)>
^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:646:17: error:
no template named 'numeric_limits'
static_assert(numeric_limits<_FloatT>::radix == 2, "FloatT has incorrect radix");
^
fatal error: too many errors emitted, stopping now [-ferror-limit=]
20 errors generated.
Here are my system specifications.
macOS Catalina Version 10.15.2
Apple clang version 11.0.3 (clang-1103.0.32.29)
Xcode Version 11.4 (11E146) (not sure if this matters)
Thanks for any assistance!
EDIT: Updated to macOS 10.15.4 and Xcode 11.4.1 and still have the same issue

Answer 1

I believe this is answered at Catalina C++: Using <cmath> headers yield error: no member named 'signbit' in the global namespace
The easiest solution seems to be to uninstall the Command Line Tools, which works on Catalina, but I was hitting this on High Sierra, where I resorted to editing /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/include/c++/v1/cmath
to comment out #include <math.h> and replace it with:
#include</Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/include/c++/v1/math.h>
I had to do this to get homebrew's Rust (rustc-1.53.0) to compile on High Sierra. Probably a better approach would be to tell cmake:
set(CMAKE_OSX_SYSROOT /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk)
since it's not usually a great idea to mess with the system-supplied headers.