I have been trying to compile a very simple code that contains postgres, pthread and mutexes. now when I do it with pthread alone every thing is fine, same when I do it with postgress alone! but when I try to compile the complete code I'm running into stupid probems!
gcc -o pleaseWork uploadData.c -I/usr/include/postgresql -lpthread -lpq
I get :
/tmp/ccitU5mG.o: In function `increaseQueryNum':
uploadData.c:(.text+0x5): relocation truncated to fit: R_X86_64_32 against symbol `counterMutex' defined in COMMON section in /tmp/ccitU5mG.o
uploadData.c:(.text+0x21): relocation truncated to fit: R_X86_64_32 against symbol `counterMutex' defined in COMMON section in /tmp/ccitU5mG.o
/tmp/ccitU5mG.o: In function `increaseStackNum':
uploadData.c:(.text+0x31): relocation truncated to fit: R_X86_64_32 against symbol `stackMutex' defined in COMMON section in /tmp/ccitU5mG.o
uploadData.c:(.text+0x4a): relocation truncated to fit: R_X86_64_32 against symbol `stackMutex' defined in COMMON section in /tmp/ccitU5mG.o
/tmp/ccitU5mG.o: In function `decreaseStackNum':
uploadData.c:(.text+0x5a): relocation truncated to fit: R_X86_64_32 against symbol `stackMutex' defined in COMMON section in /tmp/ccitU5mG.o
uploadData.c:(.text+0x73): relocation truncated to fit: R_X86_64_32 against symbol `stackMutex' defined in COMMON section in /tmp/ccitU5mG.o
/tmp/ccitU5mG.o: In function `pop':
uploadData.c:(.text+0xca): relocation truncated to fit: R_X86_64_32 against symbol `stackPopMutex' defined in COMMON section in /tmp/ccitU5mG.o
uploadData.c:(.text+0xf7): relocation truncated to fit: R_X86_64_32 against symbol `stackPopMutex' defined in COMMON section in /tmp/ccitU5mG.o
collect2: error: ld returned 1 exit status
when I run :
gcc -o omido -I/usr/include/postgresql -lpq -lpthread uploadData.c
I get :
/tmp/ccdXHrz3.o: In function `main':
uploadData.c:(.text+0x5df): undefined reference to `PQconnectdb'
uploadData.c:(.text+0x5f5): undefined reference to `PQstatus'
uploadData.c:(.text+0x613): undefined reference to `PQfinish'
uploadData.c:(.text+0x68c): undefined reference to `pthread_create'
uploadData.c:(.text+0x6d5): undefined reference to `pthread_create'
uploadData.c:(.text+0x6fe): undefined reference to `pthread_join'
uploadData.c:(.text+0x727): undefined reference to `pthread_join'
collect2: error: ld returned 1 exit status
the closest thing I have got to a compilation was (in terms of number of errors) :
gcc -o pleaseWork -I/usr/include/postgresql -pthread -lpthread -lpq uploadData.c
which results in :
/tmp/ccg6RbUk.o: In function `main':
uploadData.c:(.text+0x5df): undefined reference to `PQconnectdb'
uploadData.c:(.text+0x5f5): undefined reference to `PQstatus'
uploadData.c:(.text+0x613): undefined reference to `PQfinish'
collect2: error: ld returned 1 exit status
i don't know if it helps but here's the same command with -v:
COLLECT_GCC_OPTIONS='-s' '-o' 'omido' '-I' '/usr/include/postgresql' '-pthread' '-v' '-mtune=generic' '-march=x86-64'
as -v -I /usr/include/postgresql --64 -o /tmp/ccY3zbjH.o /tmp/ccdK2fuu.s
GNU assembler version 2.24 (x86_64-linux-gnu) using BFD version (GNU Binutils for Ubuntu) 2.24
COMPILER_PATH=/usr/lib/gcc/x86_64-linux-gnu/4.8/:/usr/lib/gcc/x86_64-linux-gnu/4.8/:/usr/lib/gcc/x86_64-linux-gnu/:/usr/lib/gcc/x86_64-linux-gnu/4.8/:/usr/lib/gcc/x86_64-linux-gnu/
LIBRARY_PATH=/usr/lib/gcc/x86_64-linux-gnu/4.8/:/usr/lib/gcc/x86_64-linux-gnu/4.8/../../../x86_64-linux-gnu/:/usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../lib/:/lib/x86_64-linux-gnu/:/lib/../lib/:/usr/lib/x86_64-linux-gnu/:/usr/lib/../lib/:/usr/lib/gcc/x86_64-linux-gnu/4.8/../../../:/lib/:/usr/lib/
COLLECT_GCC_OPTIONS='-s' '-o' 'omido' '-I' '/usr/include/postgresql' '-pthread' '-v' '-mtune=generic' '-march=x86-64'
/usr/lib/gcc/x86_64-linux-gnu/4.8/collect2 --sysroot=/ --build-id --eh-frame-hdr -m elf_x86_64 --hash-style=gnu --as-needed -dynamic-linker /lib64/ld-linux-x86-64.so.2 -z relro -o omido -s /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../x86_64-linux-gnu/crt1.o /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../x86_64-linux-gnu/crti.o /usr/lib/gcc/x86_64-linux-gnu/4.8/crtbegin.o -L/usr/lib/gcc/x86_64-linux-gnu/4.8 -L/usr/lib/gcc/x86_64-linux-gnu/4.8/../../../x86_64-linux-gnu -L/usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../lib -L/lib/x86_64-linux-gnu -L/lib/../lib -L/usr/lib/x86_64-linux-gnu -L/usr/lib/../lib -L/usr/lib/gcc/x86_64-linux-gnu/4.8/../../.. -lpq -lpthread /tmp/ccY3zbjH.o -lgcc --as-needed -lgcc_s --no-as-needed -lpthread -lc -lgcc --as-needed -lgcc_s --no-as-needed /usr/lib/gcc/x86_64-linux-gnu/4.8/crtend.o /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../x86_64-linux-gnu/crtn.o
/tmp/ccY3zbjH.o: In function `main':
uploadData.c:(.text+0x5df): undefined reference to `PQconnectdb'
uploadData.c:(.text+0x5f5): undefined reference to `PQstatus'
uploadData.c:(.text+0x613): undefined reference to `PQfinish'
collect2: error: ld returned 1 exit status
no luck so far :( does any body know what is wrong here?
here is a simplified version of my code :
#include <pthread.h>
#include <libpq-fe.h>
#include <time.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <string.h>
pthread_mutex_t stackWaitMutex;
pthread_mutex_t stackMutex;
pthread_mutex_t counterMutex;
pthread_mutex_t stackPushMutex;
pthread_mutex_t stackPopMutex;
int done=0;
long queryNum=0;
char *nameStack[500];
char *valueStack[500];
char stack[100000][100000];
int stackCounter=0;
void increaseQueryNum(){
pthread_mutex_lock(&counterMutex);
queryNum++;
pthread_mutex_unlock(&counterMutex);
}
void increaseStackNum(){
pthread_mutex_lock(&stackMutex);
stackCounter++;
pthread_mutex_unlock(&stackMutex);
}
void decreaseStackNum(){
pthread_mutex_lock(&stackMutex);
stackCounter--;
pthread_mutex_unlock(&stackMutex);
}
void push( int StackNumber, char* item ){
strcpy(stack[stackCounter ], item);
increaseStackNum();
}
char* pop ( int StackNumber ){
char *ret;
// while(lock)
// usleep(2);
pthread_mutex_lock(&stackPopMutex);
decreaseStackNum();
ret = stack[stackCounter];
// lock=0;
pthread_mutex_unlock(&stackPopMutex);
return ret;
}
void *doSeperation ( void* args ){
while(1)
{
char *p = pop(0);
if( p==NULL && done ){
return;
}
}
}
void *reader (void *args){
int i;
for( i = 0 ; i <12; i++ ){
push(1, "test!");
}
done=1;
}
int main( int argC , char** argV ){
int i;
PGconn* connection = PQconnectdb("host=XXXXXX dbname=XXXXX user=postgres password=XXXX");
if (PQstatus(connection) == CONNECTION_BAD) {
printf("Connection error\n");
PQfinish(connection);
return -1;
}
printf("Connection ok\n");
int maxThread =5;
int FilesCount =5;
pthread_t threads[1000] ;
pthread_t p2;
pthread_create(&p2,NULL,reader,&FilesCount);
usleep(60);
for( i = 0 ; i < maxThread; i++ ){
pthread_create(&threads[i],NULL,doSeperation,NULL);
}
pthread_join(p2,NULL);
for( i = 0 ; i < maxThread; i ++ ){
pthread_join(threads[i],NULL);
}
return 0;
}
This code failed to build as-is for me, due to errors such as:
I solved that by reducing the stack array by a few orders of magnitude. Your linker errors could be related, as I had no trouble linking the example after making that change.
You should compile your code with -Wall. There are several critical bugs, such as a non-void function that doesn't return a value, being used as input to pthread_create.