diff --git a/Makefile.am b/Makefile.am
index 00133f6d..79015775 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -20,8 +20,7 @@ LIBJQ_SRC = src/builtin.c src/bytecode.c src/compile.c src/execute.c    \
 ### C build options
 
 AM_CFLAGS = -Wextra -Wall -Wno-missing-field-initializers               \
-	-Wno-unused-parameter -Wno-unused-function			\
-	-Wno-cast-function-type
+	-Wno-unused-parameter -Wno-unused-function
 
 if WIN32
 AM_CFLAGS += -municode
diff --git a/src/builtin.c b/src/builtin.c
index 09ffc041..26205f91 100644
--- a/src/builtin.c
+++ b/src/builtin.c
@@ -1704,96 +1704,96 @@ static jv f_current_line(jq_state *jq, jv a) {
 }
 
 #define LIBM_DD(name) \
-  {(cfunction_ptr)f_ ## name,  #name, 1},
+  {f_ ## name,  #name, 1},
 #define LIBM_DD_NO(name)
 
 #define LIBM_DDD(name) \
-  {(cfunction_ptr)f_ ## name, #name, 3},
+  {f_ ## name, #name, 3},
 #define LIBM_DDD_NO(name)
 
 #define LIBM_DDDD(name) \
-  {(cfunction_ptr)f_ ## name, #name, 4},
+  {f_ ## name, #name, 4},
 #define LIBM_DDDD_NO(name)
 
 static const struct cfunction function_list[] = {
 #include "libm.h"
 #ifdef HAVE_FREXP
-  {(cfunction_ptr)f_frexp,"frexp", 1},
+  {f_frexp,"frexp", 1},
 #endif
 #ifdef HAVE_MODF
-  {(cfunction_ptr)f_modf,"modf", 1},
+  {f_modf,"modf", 1},
 #endif
 #ifdef HAVE_LGAMMA_R
-  {(cfunction_ptr)f_lgamma_r,"lgamma_r", 1},
+  {f_lgamma_r,"lgamma_r", 1},
 #endif
-  {(cfunction_ptr)f_plus, "_plus", 3},
-  {(cfunction_ptr)f_negate, "_negate", 1},
-  {(cfunction_ptr)f_minus, "_minus", 3},
-  {(cfunction_ptr)f_multiply, "_multiply", 3},
-  {(cfunction_ptr)f_divide, "_divide", 3},
-  {(cfunction_ptr)f_mod, "_mod", 3},
-  {(cfunction_ptr)f_dump, "tojson", 1},
-  {(cfunction_ptr)f_json_parse, "fromjson", 1},
-  {(cfunction_ptr)f_tonumber, "tonumber", 1},
-  {(cfunction_ptr)f_tostring, "tostring", 1},
-  {(cfunction_ptr)f_keys, "keys", 1},
-  {(cfunction_ptr)f_keys_unsorted, "keys_unsorted", 1},
-  {(cfunction_ptr)f_startswith, "startswith", 2},
-  {(cfunction_ptr)f_endswith, "endswith", 2},
-  {(cfunction_ptr)f_ltrimstr, "ltrimstr", 2},
-  {(cfunction_ptr)f_rtrimstr, "rtrimstr", 2},
-  {(cfunction_ptr)f_string_split, "split", 2},
-  {(cfunction_ptr)f_string_explode, "explode", 1},
-  {(cfunction_ptr)f_string_implode, "implode", 1},
-  {(cfunction_ptr)f_string_indexes, "_strindices", 2},
-  {(cfunction_ptr)f_setpath, "setpath", 3}, // FIXME typechecking
-  {(cfunction_ptr)f_getpath, "getpath", 2},
-  {(cfunction_ptr)f_delpaths, "delpaths", 2},
-  {(cfunction_ptr)f_has, "has", 2},
-  {(cfunction_ptr)f_equal, "_equal", 3},
-  {(cfunction_ptr)f_notequal, "_notequal", 3},
-  {(cfunction_ptr)f_less, "_less", 3},
-  {(cfunction_ptr)f_greater, "_greater", 3},
-  {(cfunction_ptr)f_lesseq, "_lesseq", 3},
-  {(cfunction_ptr)f_greatereq, "_greatereq", 3},
-  {(cfunction_ptr)f_contains, "contains", 2},
-  {(cfunction_ptr)f_length, "length", 1},
-  {(cfunction_ptr)f_utf8bytelength, "utf8bytelength", 1},
-  {(cfunction_ptr)f_type, "type", 1},
-  {(cfunction_ptr)f_isinfinite, "isinfinite", 1},
-  {(cfunction_ptr)f_isnan, "isnan", 1},
-  {(cfunction_ptr)f_isnormal, "isnormal", 1},
-  {(cfunction_ptr)f_infinite, "infinite", 1},
-  {(cfunction_ptr)f_nan, "nan", 1},
-  {(cfunction_ptr)f_sort, "sort", 1},
-  {(cfunction_ptr)f_sort_by_impl, "_sort_by_impl", 2},
-  {(cfunction_ptr)f_group_by_impl, "_group_by_impl", 2},
-  {(cfunction_ptr)f_min, "min", 1},
-  {(cfunction_ptr)f_max, "max", 1},
-  {(cfunction_ptr)f_min_by_impl, "_min_by_impl", 2},
-  {(cfunction_ptr)f_max_by_impl, "_max_by_impl", 2},
-  {(cfunction_ptr)f_error, "error", 1},
-  {(cfunction_ptr)f_format, "format", 2},
-  {(cfunction_ptr)f_env, "env", 1},
-  {(cfunction_ptr)f_halt, "halt", 1},
-  {(cfunction_ptr)f_halt_error, "halt_error", 2},
-  {(cfunction_ptr)f_get_search_list, "get_search_list", 1},
-  {(cfunction_ptr)f_get_prog_origin, "get_prog_origin", 1},
-  {(cfunction_ptr)f_get_jq_origin, "get_jq_origin", 1},
-  {(cfunction_ptr)f_match, "_match_impl", 4},
-  {(cfunction_ptr)f_modulemeta, "modulemeta", 1},
-  {(cfunction_ptr)f_input, "input", 1},
-  {(cfunction_ptr)f_debug, "debug", 1},
-  {(cfunction_ptr)f_stderr, "stderr", 1},
-  {(cfunction_ptr)f_strptime, "strptime", 2},
-  {(cfunction_ptr)f_strftime, "strftime", 2},
-  {(cfunction_ptr)f_strflocaltime, "strflocaltime", 2},
-  {(cfunction_ptr)f_mktime, "mktime", 1},
-  {(cfunction_ptr)f_gmtime, "gmtime", 1},
-  {(cfunction_ptr)f_localtime, "localtime", 1},
-  {(cfunction_ptr)f_now, "now", 1},
-  {(cfunction_ptr)f_current_filename, "input_filename", 1},
-  {(cfunction_ptr)f_current_line, "input_line_number", 1},
+  {f_plus, "_plus", 3},
+  {f_negate, "_negate", 1},
+  {f_minus, "_minus", 3},
+  {f_multiply, "_multiply", 3},
+  {f_divide, "_divide", 3},
+  {f_mod, "_mod", 3},
+  {f_dump, "tojson", 1},
+  {f_json_parse, "fromjson", 1},
+  {f_tonumber, "tonumber", 1},
+  {f_tostring, "tostring", 1},
+  {f_keys, "keys", 1},
+  {f_keys_unsorted, "keys_unsorted", 1},
+  {f_startswith, "startswith", 2},
+  {f_endswith, "endswith", 2},
+  {f_ltrimstr, "ltrimstr", 2},
+  {f_rtrimstr, "rtrimstr", 2},
+  {f_string_split, "split", 2},
+  {f_string_explode, "explode", 1},
+  {f_string_implode, "implode", 1},
+  {f_string_indexes, "_strindices", 2},
+  {f_setpath, "setpath", 3}, // FIXME typechecking
+  {f_getpath, "getpath", 2},
+  {f_delpaths, "delpaths", 2},
+  {f_has, "has", 2},
+  {f_equal, "_equal", 3},
+  {f_notequal, "_notequal", 3},
+  {f_less, "_less", 3},
+  {f_greater, "_greater", 3},
+  {f_lesseq, "_lesseq", 3},
+  {f_greatereq, "_greatereq", 3},
+  {f_contains, "contains", 2},
+  {f_length, "length", 1},
+  {f_utf8bytelength, "utf8bytelength", 1},
+  {f_type, "type", 1},
+  {f_isinfinite, "isinfinite", 1},
+  {f_isnan, "isnan", 1},
+  {f_isnormal, "isnormal", 1},
+  {f_infinite, "infinite", 1},
+  {f_nan, "nan", 1},
+  {f_sort, "sort", 1},
+  {f_sort_by_impl, "_sort_by_impl", 2},
+  {f_group_by_impl, "_group_by_impl", 2},
+  {f_min, "min", 1},
+  {f_max, "max", 1},
+  {f_min_by_impl, "_min_by_impl", 2},
+  {f_max_by_impl, "_max_by_impl", 2},
+  {f_error, "error", 1},
+  {f_format, "format", 2},
+  {f_env, "env", 1},
+  {f_halt, "halt", 1},
+  {f_halt_error, "halt_error", 2},
+  {f_get_search_list, "get_search_list", 1},
+  {f_get_prog_origin, "get_prog_origin", 1},
+  {f_get_jq_origin, "get_jq_origin", 1},
+  {f_match, "_match_impl", 4},
+  {f_modulemeta, "modulemeta", 1},
+  {f_input, "input", 1},
+  {f_debug, "debug", 1},
+  {f_stderr, "stderr", 1},
+  {f_strptime, "strptime", 2},
+  {f_strftime, "strftime", 2},
+  {f_strflocaltime, "strflocaltime", 2},
+  {f_mktime, "mktime", 1},
+  {f_gmtime, "gmtime", 1},
+  {f_localtime, "localtime", 1},
+  {f_now, "now", 1},
+  {f_current_filename, "input_filename", 1},
+  {f_current_line, "input_line_number", 1},
 };
 #undef LIBM_DDDD_NO
 #undef LIBM_DDD_NO
diff --git a/src/bytecode.h b/src/bytecode.h
index 6cb49f7a..15019852 100644
--- a/src/bytecode.h
+++ b/src/bytecode.h
@@ -45,9 +45,8 @@ const struct opcode_description* opcode_describe(opcode op);
 
 
 #define MAX_CFUNCTION_ARGS 10
-typedef void (*cfunction_ptr)();
 struct cfunction {
-  cfunction_ptr fptr;
+  jv (*fptr)();
   const char* name;
   int nargs;
 };
diff --git a/src/execute.c b/src/execute.c
index 78910077..86def927 100644
--- a/src/execute.c
+++ b/src/execute.c
@@ -914,17 +914,12 @@ jv jq_next(jq_state *jq) {
         in[i] = stack_pop(jq);
       }
       struct cfunction* function = &frame_current(jq)->bc->globals->cfunctions[*pc++];
-      typedef jv (*func_1)(jq_state*,jv);
-      typedef jv (*func_2)(jq_state*,jv,jv);
-      typedef jv (*func_3)(jq_state*,jv,jv,jv);
-      typedef jv (*func_4)(jq_state*,jv,jv,jv,jv);
-      typedef jv (*func_5)(jq_state*,jv,jv,jv,jv,jv);
       switch (function->nargs) {
-      case 1: top = ((func_1)function->fptr)(jq, in[0]); break;
-      case 2: top = ((func_2)function->fptr)(jq, in[0], in[1]); break;
-      case 3: top = ((func_3)function->fptr)(jq, in[0], in[1], in[2]); break;
-      case 4: top = ((func_4)function->fptr)(jq, in[0], in[1], in[2], in[3]); break;
-      case 5: top = ((func_5)function->fptr)(jq, in[0], in[1], in[2], in[3], in[4]); break;
+      case 1: top = function->fptr(jq, in[0]); break;
+      case 2: top = function->fptr(jq, in[0], in[1]); break;
+      case 3: top = function->fptr(jq, in[0], in[1], in[2]); break;
+      case 4: top = function->fptr(jq, in[0], in[1], in[2], in[3]); break;
+      case 5: top = function->fptr(jq, in[0], in[1], in[2], in[3], in[4]); break;
       // FIXME: a) up to 7 arguments (input + 6), b) should assert
       // because the compiler should not generate this error.
       default: return jv_invalid_with_msg(jv_string("Function takes too many arguments"));