error: unknown type name ‘Point’

Question

When I try to compile a C file under 64-bit Linux using command:

gcc -o strain_from_faults_new strain_from_faults_new.c gen.h eqf.h

I met the following errors:

eqf.h:16:3: error: unknown type name ‘Point’
   Point loc; 
   ^
eqf.h:32:3: error: unknown type name ‘Point’
   Point p[33]; 
   ^
eqf.h:44:3: error: unknown type name ‘Point’
   Point p[33]; 
   ^
eqf.h:61:3: error: unknown type name ‘Point’
   Point xy[NSEG]; 
   ^

It seems that type 'Point' is not defined, but it does defined in the file

gen.h

struct point {
  double x;
  double y;
 };
typedef struct point Point;

I don't know why it have such an error, since this C file can be compiled in other computers. Is this 32bit-64bit compatible issue? Any comment(s) would be highly appreciated!

According to the comments I #include "gen.h" in eqf.h file, but it not doing well. Since the two head files gen.h eqf.h have already been included in the C file strain_from_faults_new.c, the compiler have errors:

In file included from eqf.h:12:0,
                 from strain_from_faults_new.c:6:
gen.h:11:8: error: redefinition of ‘struct point’
 struct point {
        ^
In file included from strain_from_faults_new.c:5:0:
gen.h:11:8: note: originally defined here
 struct point {
        ^

Does anybody have any ideas?

Well, following are the entire codes:

gen.h

#define MAX_NAME 50
#define MAXNAME 50
#define EARTH_RADIUS 6371.0
#define MU (3.0e11)
#define PI 3.1415927
#define D2R 0.0174532
#define SUNIT (1.0e-9)
#define KAPA 0.25
#include <stdio.h>

struct point {
  double x;
  double y;
};

typedef struct point Point;

extern int enclose(Point *, int, Point);
extern int enclose2(Point *, int, Point, Point);
extern int lenclose(Point *p, int n, Point p1);
extern int lenclose2(Point *p, int n, Point p1, Point p2);
extern double azimuth(double, double);
extern double atan2d(double, double);
extern double sind(double);
extern double cosd(double);
extern double dsign(double);
extern double dmax(double, double);
extern double dmin(double, double);
extern double diag_len(Point p[]);
extern void make_tensor(double z[][3],  double, double, double);
extern void read_a_line(FILE *);
extern void strip_a_line(FILE *);
extern char *get_a_string(FILE *f, char* str);
extern int line_to_string(FILE *f, char* str);
extern int in_region(int node[], int N, int p);
extern double convert_date_to_year(int);

eqf.h

#define MAXP 10
#define MAXN 400
#define MAXB 1000
#define MAXF 37000
#define MAXE 1000
#define TYPE_F 1
#define TYPE_E 0
#define T 149 
#define DEPTH 15.0 
#define NSEG 2074
#include <stdio.h>
#include "gen.h"


struct earthquake {
  int  date;
  Point loc; 
  double mom[3][3];
  double m0;
  int type;
};
struct merr {
  double m[3][3];
};

struct mom {
  double m0;
  double mxx;
  double myy;
  double mxy;
};
struct region {
  Point p[33]; 
  double area; 
  double t0; 
  struct earthquake event[50];
  int ne; 
  struct earthquake *e[100];
  double strainrate[9]; 
  double strain[9]; 
  double strainr[9]; 
  double strain0[9]; 
};
 struct regionf {
   Point p[33]; 
   double area; 
   int ix;
   int iy;
   int ia;
};

 struct fault {
   double strike;
   double rake;
   double dip;
   double rate;
   double ratemin;
   double ratemax;
   char name[50];
   int  date;
   int n; 
   Point xy[NSEG]; 
 };

 extern void test();
 extern void read_faults(FILE *inf, struct fault *f);
 extern void test_mom();
 extern void print_event (FILE *inf, struct earthquake e);
 extern int bydate(struct earthquake *, struct earthquake *);
 extern void sort_event(FILE *);
 extern int write_mom_tensor(struct earthquake *, int *, double);
 extern void fill_regionf(struct regionf *, int *);
 extern void fill_region(struct region *, int *);
 extern void print_mom_in_region(struct region *b, int nb);
 extern double strain_rate(double ex, double ey, double exy);
 extern double strain_rate_var(double ex, double ey, double exy, double dex, double dey, double dexy, double cxy, double cxxy, double cyxy);

strain_from_faults_new.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include "gen.h"
#include "eqf.h"

void deal_with_options(int, char **);

int no_faults, n_events;
double sdepth;
double ub = 0.01;
char faultin[25];
FILE *strain1;

int main(int argc, char *argv[]) {
  Point p[MAXN], p1[10];
  struct fault f[MAXF];
  struct regionf b[MAXB];
  double  plat=0.0, plon=0.0, prat=0.0;
  int n=0, i, j, nb=0, np, num, ia, k, l, nrect=0, nfree=0, ix=0, iy=0;
  FILE *faults, *strain0;

  sdepth = DEPTH*1.0e5;
  strcpy(faultin, "fault.in");

  deal_with_options(argc, argv);

  if( (faults = fopen(faultin, "r")) == NULL ) {
     printf("Error: File %s does not exist.\n", faultin);
     exit(-1);
  }
  if( (strain0 = fopen("spline_fit.dat", "r")) == NULL) {
     printf("Error: File spline_fit.dat cannot open\n");
     exit(-1);
  }
  if( (strain1 = fopen("strain_from_faults.dat", "w")) == NULL) {
     printf("Error: File strain_from_faults.dat cannot open\n");
     exit(-1);
  }

  fscanf(strain0, "%d%d%d", &ix, &iy, &num);
  fscanf(strain0, "%d", &nfree);
  fprintf(strain1, "%10d %10d %10d\n", ix, iy, num);
  fprintf(strain1, "%10d\n", nfree);
  for(i=nfree; i<num; i++) {
    if(fscanf(strain0, "%d%lf%lf%lf",  &np, &plat, &plon, &prat) != 4) {
      printf("Error: format error in spline_fit.dat\n");
      exit(1);
     }
     fprintf(strain1, "%10d %10.3f %10.3f %12.6e\n", np, plat, plon, prat);

     }
     fscanf(strain0, "%d", &nrect);
     fprintf(strain1, "%10d\n", nrect);
     close(strain0);

     for(i = 0; i < nrect; i += MAXB) {
       nb = i;
       printf("Working on regions %d to %d ...\n", i, i+MAXB);
       fill_regionf(b, &nb);
       read_clip_faults(faults, f, b, nb);   
     }
     return 0;
 }


 int read_clip_faults(FILE *inf, struct fault *f, struct regionf *b, int nb) {
 int i, j, k, l, ib, jj, kk, ii, n, nf;
 double x, y, dx, dy, d, mt[3][3], c, theta;
 double sd, md, strainrate[9];
 double clip_seg = 0.05;
 struct mom m1;
 struct mom m0;
 struct merr m2;
 struct fault f0;
 Point p[100], p0;

 i=0;
 fseek(inf, 0, SEEK_SET);
 while( (k = fscanf(inf, "%d%lf%lf%lf%lf%lf%s",
        &n, &(f[i].rake), &(f[i].dip), &(f[i].ratemin),
         &(f[i].rate), &(f[i].ratemax), f[i].name)) == 7) {
     printf("Fault no. %d, %s\n", i, f[i].name);

   f[i].rate = f[i].rate;
   f[i].ratemin = f[i].ratemin;
   f[i].ratemax = f[i].ratemax;
   f[i].n = 0;

   for(j=0; j<n; j++) {
     if( (l = fscanf(inf, "%lf%lf", &(p[j].y), &(p[j].x))) != 2) {
       printf("Error at fault %s, line %d in fault.in\n", f[i].name, j);
       exit(1);
     }
   }

   jj=0;
  for(j=0; j<n-1; j++) {
k = 0;
while( k < nb && (l = enclose(b[k].p, 33, p[j])) == 0)
...

Following Mike Kinghan's comments, I added

#ifndef GEN_H
#define GEN_H

and

#endif

in the head and tail of the gen.h file, respectively. But it not doing well, here are the errors:

/tmp/ccteT25z.o: In function `read_clip_faults':
strain_from_faults_new.c:(.text+0x6a4): undefined reference to `enclose'
strain_from_faults_new.c:(.text+0x7c5): undefined reference to `enclose'
strain_from_faults_new.c:(.text+0xa14): undefined reference to `enclose'
strain_from_faults_new.c:(.text+0xa7b): undefined reference to `dsign'
strain_from_faults_new.c:(.text+0xaae): undefined reference to `dsign'
strain_from_faults_new.c:(.text+0xad9): undefined reference to `dsign'
strain_from_faults_new.c:(.text+0xb5a): undefined reference to `dsign'
...

This update confirms that the answer is as I've expained below. — Mike Kinghan, Mar 02 '16 at 15:02
Your latest errors are *linkage* errors. See [this question](http://stackoverflow.com/q/12573816/1362568). Read the [accepted answer](http://stackoverflow.com/a/12573818/1362568) and apply [the top Common Cause](http://stackoverflow.com/a/12574400/1362568) to your errors. — Mike Kinghan, Mar 02 '16 at 17:45

score 4 · Answer 1 · answered Mar 02 '16 at 04:15

4

you need to #include "gen.h" in eqf.h

answered Mar 02 '16 at 04:15

sunny1304

1,684
3
17
30

Thank you, but the head files have already include in the C file. If I include the gen.h in eqf.h, the compiler come errors with "gen.h:11:8: error: redefinition of 'struct point' " – joe Mar 02 '16 at 13:53
does struct point is is defined separately in both gen.h and eqf.h ?? is so then you need to remove struct point definition from any of the header file. – sunny1304 Mar 02 '16 at 14:19
No, the struct point is only defined in the gen.h file. I updated my question, and I thought the problem is the two head files have been included in the C file. – joe Mar 02 '16 at 14:23
can you post all the codes ? it will easier to provide a solution. – sunny1304 Mar 02 '16 at 14:25

score 0 · Accepted Answer · answered Mar 02 '16 at 14:38

0

If you read this:

In file included from eqf.h:12:0,
                 from strain_from_faults_new.c:6:
gen.h:11:8: error: redefinition of ‘struct point’
 struct point {
        ^
In file included from strain_from_faults_new.c:5:0:
gen.h:11:8: note: originally defined here
 struct point {
        ^

it tells you that struct point is defined twice in the same translation unit, strain_from_faults_new.c, which is an error.

You have defined struct point in gen.h at line 11.

You have included gen.h at line 5 in strain_from_faults_new.c

You have also included gen.h at line 12 in eqf.h.

And finally you have included eqf.h at line 6 in strain_from_faults_new.c, thereby including the definition of struct point again.

To avoid such problems, use header guards a.k.a include guards in every header you write, e.g.

gen.h

#ifndef GEN_H
#define GEN_H

    struct point {
      double x;
      double y;
     };
    typedef struct point Point;

#endif

This makes it harmless to include a header more than once in a translation unit.

And, don't pass header files in the compiler commandline:

gcc -o strain_from_faults_new strain_from_faults_new.c gen.h eqf.h
                                                       ^^^^^ ^^^^^

A header file gets compiled by being #include-ed in a .c file, which copies it into the translation unit.

answered Mar 02 '16 at 14:38

Mike Kinghan

55,740
12
153
182

Thank you so much, but it seems some of functions defined in the gen.h cannot be recognized in the C file. /tmp/ccteT25z.o: In function `read_clip_faults': strain_from_faults_new.c:(.text+0x6a4): undefined reference to `enclose' . And I will update the question at now – joe Mar 02 '16 at 15:14
Welcome to StackOverflow. The problem you posted is solved. In that case you should [accept](http://stackoverflow.com/help/accepted-answer) an answer. The solution has enabled you to discover a new problem, so ask a new question, if you can't solve it yourself. You cannot keep changing one SO question to get answers to an open-ended series of problems. – Mike Kinghan Mar 02 '16 at 15:22
Thanks for your help, it will be great if you can take a look at the errors that occurred after adding the header guards in gen.h file – joe Mar 02 '16 at 15:41
Sorry Joe, can only repeat my last comment. You're not playing by the rules of this site. – Mike Kinghan Mar 02 '16 at 16:02
Thanks for your advices – joe Mar 02 '16 at 17:13

score -2 · Answer 3 · edited Mar 02 '16 at 09:19

-2

You need to add #include "gen.h" in eqf.h and compile your program with the command:
gcc -o gen.h eqf.h strain_from_faults_new strain_from_faults_new.c;

Compiler will compile your program file according to your file input order.

edited Mar 02 '16 at 09:19

Anmol Singh Jaggi

8,376
4
36
77

answered Mar 02 '16 at 08:53

gehan

19
3

error: unknown type name ‘Point’

3 Answers3