Disable BB GMP and MPFR, to fix performance regressions

Make.inc

@@ -940,9 +940,13 @@ USE_BINARYBUILDER := 0
 endif
 
 # This is the set of projects that BinaryBuilder dependencies are hooked up for.
-BB_PROJECTS := OPENBLAS LLVM SUITESPARSE OPENLIBM GMP MBEDTLS LIBSSH2 MPFR CURL LIBGIT2 PCRE LIBUV UNWIND
+BB_PROJECTS := OPENBLAS LLVM SUITESPARSE OPENLIBM MBEDTLS LIBSSH2 CURL LIBGIT2 PCRE LIBUV UNWIND
 $(foreach proj,$(BB_PROJECTS),$(if $(USE_BINARYBUILDER_$(proj)),,$(eval USE_BINARYBUILDER_$(proj) := $(USE_BINARYBUILDER))))
 
+# GMP and MPFR have serious performance regressions for now
+USE_BINARYBUILDER_GMP ?= 0
+USE_BINARYBUILDER_MPFR ?= 0
+
 # Use the Assertions build
 BINARYBUILDER_LLVM_ASSERTS := 0