Add MySQL to my Makefile gives problems - mysql

Question

I have a problem with my C project built under Debian Jessie. After doing some stuffs now I need to work with MySQL so i download the library and try to update my Makefile.
This is my Makefile right now
CC = gcc
CFLAGS = -Wall -Wextra
LDFLAGS = -lbluetooth -lpthread -lmysqlclient
LFLAGS = -lm
INC = -I/usr/include/mysql
SOURCES = stb.c btscan.c and.c gima.c database.c
OBJECTS = $(SOURCES:.c=.o)
EXECUTABLE = stb
$(EXECUTABLE): $(OBJECTS)
$(CC) $(CFLAGS) $(OBJECTS) -o $# $(LFLAGS) $(LDFLAGS)
stb.o: btscan.h and.h gima.h database.h
btscan.o: btscan.h
and.o: and.h
gima.o: gima.h
database.o: database.h
clean:
#rm -f *.o *.out stb
and this is the files where I want to use the library
stb.c
#include "btscan.h"
#include "and.h"
#include "gima.h"
#include "database.h"
struct device* bt_devices;
struct device* ble_devices;
int main(void) {
//-------------------------------- DATABASE CONNECTION ----------------
//MYSQL *con = mysql_init(NULL);
....... }
and finally database.h
#ifndef _DATABASE_H
#define _DATABASE_H
#include <my_global.h>
#include <mysql.h>
#endif
When I try to make i receive "Fatal error : my_global.h No such file or directory". However if i try MySQL on a single test file and compiling it with
gcc -o test test.c -I/usr/include/mysql -lmysqlclient
it works. Where I made a mistake?
Thanks in advance

Answer 1

If you'd shown us the output of the compiler, or examine it yourself, you'll immediately see that what you're running on the command line is not the same at all as what make is running: in particular make is not adding the -I/usr/include/mysql flag to the command line.
That's because in your makefile you set:
INC = -I/usr/include/mysql
but nowhere in your makefile (as you've shown it) is the variable INC actually used, so this is essentially a no-op.
Since you're using the standard GNU make compilation rules, you should be setting standard GNU make variables:
CPPFLAGS = -I/usr/include/mysql