several "'return' with no value" warnings in alchemy.c

[rabidt]

alchemy.c: In function \u2018num_of_bombs_preparable\u2019:
alchemy.c:336:5: warning: \u2018return\u2019 with no value, in function returning non-void
     return;
     ^~~~~~
alchemy.c:332:5: note: declared here
 int num_of_bombs_preparable(struct char_data *ch)
     ^~~~~~~~~~~~~~~~~~~~~~~
alchemy.c: In function \u2018num_of_bombs_prepared\u2019:
alchemy.c:351:5: warning: \u2018return\u2019 with no value, in function returning non-void
     return;
     ^~~~~~
alchemy.c:347:5: note: declared here
 int num_of_bombs_prepared(struct char_data *ch)
     ^~~~~~~~~~~~~~~~~~~~~
alchemy.c: In function \u2018find_open_bomb_slot\u2019:
alchemy.c:469:5: warning: \u2018return\u2019 with no value, in function returning non-void
     return;
     ^~~~~~
alchemy.c:465:5: note: declared here
 int find_open_bomb_slot(struct char_data *ch)
     ^~~~~~~~~~~~~~~~~~~
alchemy.c: In function \u2018can_learn_discovery\u2019:
alchemy.c:1646:5: warning: \u2018return\u2019 with no value, in function returning non-void
     return;
     ^~~~~~
alchemy.c:1642:5: note: declared here
 int can_learn_discovery(struct char_data *ch, int discovery)
     ^~~~~~~~~~~~~~~~~~~
alchemy.c: In function \u2018num_alchemical_discoveries_known\u2019:
alchemy.c:1756:5: warning: \u2018return\u2019 with no value, in function returning non-void
     return;
     ^~~~~~
alchemy.c:1752:5: note: declared here
 int num_alchemical_discoveries_known(struct char_data *ch)
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
alchemy.c: In function \u2018list_alchemical_discoveries\u2019:
alchemy.c:1813:5: warning: \u2018return\u2019 with no value, in function returning non-void
     return;
     ^~~~~~
alchemy.c:1809:5: note: declared here
 int list_alchemical_discoveries(struct char_data *ch)
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~
alchemy.c: In function \u2018can_swallow\u2019:
alchemy.c:2022:5: warning: \u2018return\u2019 with no value, in function returning non-void
     return;
     ^~~~~~
In file included from alchemy.c:7:0:
alchemy.c:2018:11: note: declared here
 ACMDCHECK(can_swallow)
           ^
utils.h:44:7: note: in definition of macro \u2018ACMDCHECK\u2019
   int name(struct char_data *ch, bool show_error)
       ^~~~
alchemy.c: In function \u2018display_discovery_info\u2019:
alchemy.c:3070:5: warning: \u2018return\u2019 with no value, in function returning non-void
     return;
     ^~~~~~
alchemy.c:3066:6: note: declared here
 bool display_discovery_info(struct char_data *ch, char *discoveryname)
      ^~~~~~~~~~~~~~~~~~~~~~
alchemy.c: In function \u2018display_grand_discovery_info\u2019:
alchemy.c:3157:5: warning: \u2018return\u2019 with no value, in function returning non-void
     return;
     ^~~~~~
alchemy.c:3153:6: note: declared here
 bool display_grand_discovery_info(struct char_data *ch, char *discoveryname)
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
alchemy.c: In function \u2018display_bomb_types\u2019:
alchemy.c:3207:5: warning: \u2018return\u2019 with no value, in function returning non-void
     return;
     ^~~~~~
alchemy.c:3203:6: note: declared here
 bool display_bomb_types(struct char_data *ch, char *keyword)
      ^~~~~~~~~~~~~~~~~~
alchemy.c: In function \u2018display_discovery_types\u2019:
alchemy.c:3244:5: warning: \u2018return\u2019 with no value, in function returning non-void
     return;
     ^~~~~~
alchemy.c:3240:6: note: declared here
 bool display_discovery_types(struct char_data *ch, char *keyword)