Bug 23632 – [ImportC] undefined identifier `_Float128`

Here's the full code of mathcalls-helper-functions.h: /* Classify given number. */ __MATHDECL_ALIAS (int, __fpclassify,, (_Mdouble_ __value), fpclassify) __attribute__ ((__const__)); /* Test for negative number. */ __MATHDECL_ALIAS (int, __signbit,, (_Mdouble_ __value), signbit) __attribute__ ((__const__)); /* Return 0 if VALUE is finite or NaN, +1 if it is +Infinity, -1 if it is -Infinity. */ __MATHDECL_ALIAS (int, __isinf,, (_Mdouble_ __value), isinf) __attribute__ ((__const__)); /* Return nonzero if VALUE is finite and not NaN. Used by isfinite macro. */ __MATHDECL_ALIAS (int, __finite,, (_Mdouble_ __value), finite) __attribute__ ((__const__)); /* Return nonzero if VALUE is not a number. */ __MATHDECL_ALIAS (int, __isnan,, (_Mdouble_ __value), isnan) __attribute__ ((__const__)); /* Test equality. */ __MATHDECL_ALIAS (int, __iseqsig,, (_Mdouble_ __x, _Mdouble_ __y), iseqsig); /* Test for signaling NaN. */ __MATHDECL_ALIAS (int, __issignaling,, (_Mdouble_ __value), issignaling) __attribute__ ((__const__)); And here's the error message: In file included from <command-line>: /home/gunther/place/dlang/dmd/generated/linux/debug/64/../../../../druntime/import/importc.h:80:8: warning: undefining "__has_builtin" 80 | #undef __has_builtin | ^~~~~~~~~~~~~ /usr/include/x86_64-linux-gnu/bits/mathcalls-helper-functions.h(21): Error: undefined identifier `_Float128` /usr/include/x86_64-linux-gnu/bits/mathcalls-helper-functions.h(25): Error: undefined identifier `_Float128` /usr/include/x86_64-linux-gnu/bits/mathcalls-helper-functions.h(30): Error: undefined identifier `_Float128` /usr/include/x86_64-linux-gnu/bits/mathcalls-helper-functions.h(34): Error: undefined identifier `_Float128` /usr/include/x86_64-linux-gnu/bits/mathcalls-helper-functions.h(38): Error: undefined identifier `_Float128` /usr/include/x86_64-linux-gnu/bits/mathcalls-helper-functions.h(41): Error: undefined identifier `_Float128` /usr/include/x86_64-linux-gnu/bits/mathcalls-helper-functions.h(41): Error: undefined identifier `_Float128` /usr/include/x86_64-linux-gnu/bits/mathcalls-helper-functions.h(45): Error: undefined identifier `_Float128` The lines corresponding to the error message are all __attribute__ ((__const__));

I can't repro this. My Linux system does not have mathcalls-helper-functions.h, nor _Float128. The current master also compiles __attribute__((__const__)). I'm going to mark this as "worksforme". If this problem persists, feel free to reopen it, with some context.

(In reply to Walter Bright from comment #1) > I can't repro this. My Linux system does not have > mathcalls-helper-functions.h, nor _Float128. > > The current master also compiles __attribute__((__const__)). > > I'm going to mark this as "worksforme". If this problem persists, feel free > to reopen it, with some context. You must have a very old Linux system - mathcalls-helper-functions.h was added to glibc and _Float128 was added to gcc many years ago. Anyway, as you note, __attribute__((__const__)) works and _Float128 has been fixed in importc.h: https://github.com/dlang/dmd/blob/master/druntime/src/importc.h#L144 It should be closed as "fixed".