Incorrect results for convert(Float64,::Expression) and segfault for convert(BigFloat,::Expression)

[jarlebring]

A variable that is convertible to a Float64 should presumably also be convertible to BigFloat, or at least not segfault.

(@v1.11) pkg> status HomotopyContinuation
Status `~/.julia/environments/v1.11/Project.toml`
  [f213a82b] HomotopyContinuation v2.12.0

julia> using HomotopyContinuation

julia> @var x; s=x+1-x;

julia> s
1

julia> typeof(s)
Expression

julia> convert(Float64,s)
2.1219957915e-314

julia> convert(BigFloat,s)

[610525] signal 11 (1): Segmentation fault
in expression starting at REPL[10]:1
mpfr_set4 at /workspace/srcdir/mpfr-4.2.1/src/set.c:59
real_mpfr_get at /home/jarl/.julia/artifacts/7b99956590f90a608ded76e0757af76a17f8289a/lib/libsymengine.so (unknown line)
convert at /home/jarl/.julia/packages/HomotopyContinuation/HdN5z/src/model_kit/symengine.jl:705
unknown function (ip: 0x7f22d0193d43)
jl_apply at /cache/build/builder-amdci5-1/julialang/julia-master/src/julia.h:2157 [inlined]
do_call at /cache/build/builder-amdci5-1/julialang/julia-master/src/interpreter.c:126
eval_value at /cache/build/builder-amdci5-1/julialang/julia-master/src/interpreter.c:223
eval_stmt_value at /cache/build/builder-amdci5-1/julialang/julia-master/src/interpreter.c:174 [inlined]
eval_body at /cache/build/builder-amdci5-1/julialang/julia-master/src/interpreter.c:663
jl_interpret_toplevel_thunk at /cache/build/builder-amdci5-1/julialang/julia-master/src/interpreter.c:821
jl_toplevel_eval_flex at /cache/build/builder-amdci5-1/julialang/julia-master/src/toplevel.c:943
jl_toplevel_eval_flex at /cache/build/builder-amdci5-1/julialang/julia-master/src/toplevel.c:886
ijl_toplevel_eval_in at /cache/build/builder-amdci5-1/julialang/julia-master/src/toplevel.c:994
eval at ./boot.jl:430 [inlined]
eval_user_input at /cache/build/builder-amdci5-1/julialang/julia-master/usr/share/julia/stdlib/v1.11/REPL/src/REPL.jl:226
repl_backend_loop at /cache/build/builder-amdci5-1/julialang/julia-master/usr/share/julia/stdlib/v1.11/REPL/src/REPL.jl:323
#start_repl_backend#59 at /cache/build/builder-amdci5-1/julialang/julia-master/usr/share/julia/stdlib/v1.11/REPL/src/REPL.jl:308
start_repl_backend at /cache/build/builder-amdci5-1/julialang/julia-master/usr/share/julia/stdlib/v1.11/REPL/src/REPL.jl:305

[jarlebring]

In fact convert for Float64 also does not work as expected

julia> @var x; s=x+1-x;
julia> s
1
julia> Float64(s)
1.0
julia> convert(Float64,s)
2.1219957915e-314
julia> BigFloat(s)
1.0