error: static declaration of ‘json_tokener_get_parse_end’ follows non-static declaration

[matrixpool]

hi, compild libucode and output:
In file included from /opt/ucode/lib.c:45:
/opt/ucode/json-c-compat.h:28:22: error: static declaration of ‘json_tokener_get_parse_end’ follows non-static declaration
28 | static inline size_t json_tokener_get_parse_end(struct json_tokener *tok) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/json-c/json.h:30,
from /opt/ucode/json-c-compat.h:22,
from /opt/ucode/lib.c:45:
/usr/include/json-c/json_tokener.h:136:20: note: previous declaration of ‘json_tokener_get_parse_end’ with type ‘size_t(struct json_tokener *)’ {aka ‘long unsigned int(struct json_tokener *)’}
136 | JSON_EXPORT size_t json_tokener_get_parse_end(struct json_tokener *tok);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /opt/ucode/lib.c:45:
/opt/ucode/json-c-compat.h:34:35: error: static declaration of ‘json_object_new_array_ext’ follows non-static declaration
34 | static inline struct json_object *json_object_new_array_ext(int size) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/json-c/json.h:27,
from /opt/ucode/json-c-compat.h:22,
from /opt/ucode/lib.c:45:
/usr/include/json-c/json_object.h:536:33: note: previous declaration of ‘json_object_new_array_ext’ with type ‘struct json_object *(int)’
536 | JSON_EXPORT struct json_object *json_object_new_array_ext(int initial_size);
| ^~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /opt/ucode/lib.c:45:
/opt/ucode/json-c-compat.h:41:35: error: static declaration of ‘json_object_new_uint64’ follows non-static declaration
41 | static inline struct json_object *json_object_new_uint64(uint64_t i) {
| ^~~~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/json-c/json.h:27,
from /opt/ucode/json-c-compat.h:22,
from /opt/ucode/lib.c:45:
/usr/include/json-c/json_object.h:699:33: note: previous declaration of ‘json_object_new_uint64’ with type ‘struct json_object *(uint64_t)’ {aka ‘struct json_object *(long unsigned int)’}
699 | JSON_EXPORT struct json_object *json_object_new_uint64(uint64_t i);
| ^~~~~~~~~~~~~~~~~~~~~~
In file included from /opt/ucode/lib.c:45:
/opt/ucode/json-c-compat.h:45:24: error: static declaration of ‘json_object_get_uint64’ follows non-static declaration
45 | static inline uint64_t json_object_get_uint64(const struct json_object *obj) {
| ^~~~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/json-c/json.h:27,
from /opt/ucode/json-c-compat.h:22,
from /opt/ucode/lib.c:45:
/usr/include/json-c/json_object.h:773:22: note: previous declaration of ‘json_object_get_uint64’ with type ‘uint64_t(const struct json_object *)’ {aka ‘long unsigned int(const struct json_object *)’}
773 | JSON_EXPORT uint64_t json_object_get_uint64(const struct json_object *obj);
| ^~~~~~~~~~~~~~~~~~~~~~
make[2]: *** [CMakeFiles/libucode.dir/build.make:90: CMakeFiles/libucode.dir/lib.c.o] Error 1
make[1]: *** [CMakeFiles/Makefile2:128: CMakeFiles/libucode.dir/all] Error 2
make: *** [Makefile:136: all] Error 2

how to resolve?

[jow-]

Try cleaning your build tree (git clean -f -d -x), then run cmake . again to re-detect libjson-c features, then try to build again. If it still fails, you need to provide more details about your environment such as Operating System, used toolchain etc.

[thamesview]

I had the same problem with static inline vs non-static declaration errors.

I've resolved the issue by adding:

#define JSON_EXPORT static inline

before #include <json-c/json.h> in json-c-compat.h

I was following steps for building ucode for 'Other Linux systems' using:

ucode git hash 55ee75b - latest ucode commit dated 13 March 23
json-c git hash 0bc2dd5e60 - commit dated 2 March 23

git clone https://github.com/jow-/ucode.git
cd ucode/
cmake -DUBUS_SUPPORT=OFF -DUCI_SUPPORT=OFF -DULOOP_SUPPORT=OFF .
make
sudo make install

By default JSON_EXPORT is defined as extern so this generates non-static declarations for the same set of compat functions - which are in conflict with each other.

The root cause of the errors might be that:

check_symbol_exists(json_tokener_get_parse_end "json-c/json.h" HAVE_PARSE_END)
check_symbol_exists(json_object_new_array_ext "json-c/json.h" HAVE_ARRAY_EXT)
check_symbol_exists(json_object_new_uint64 "json-c/json.h" HAVE_JSON_UINT64)

are not correctly detecting presence of these functions - but I didn't have time to investigate this in more detail - just included a quick hack to define JSON_EXPORT in json-c-compat.h file : )