I am building ECL on by a compiler which doesn't have function sinl, cosl, etc.
In result ECL_LONG_FLOAT=0 (see aclocal.m4 line 9).
During compilation I have the following error:
In function 'cl_coerce': lsp/predlib.c:1947: error: 'struct cl_core_struct' has no member named 'longfloat_zero'
I suppose (based on the acloca.m4 code) this may be reproduced by passing --enable_longdouble=no to the configure.