More Compiler Errors...

[P3nGu1N]

Yes, I'm still having problems coding my SymTab.h file.

Here is what the compiler is giving me:

SymTab.h: In function 'EnterName':
SymTab.h:137: warning assignment makes pointer from integer without a cast
SymTab.h: At top level:
SymTab.h:158: error: conflicting types for 'FindName'
SymTab.h:137: error: previous implicit declaration of 'FindName' was here
SymTab.h: In function 'EnterName':
SymTab.h:137: warning: assignment makes pointer from integer without a cast
SymTab.h: At top level:

right, so I don't see where there's an integer assignment in this code at all, but maybe somebody can help me see it.

Here's the code segment that tries to do the assignment, line 137 highlighted for convenience.

bool EnterName(struct SymTab *ATable, const char *Name,
					struct SymEntry * *AnEntry) {
	int hashValue = hash(Name,ATable);
	char n[200];
	int nameLength;
	struct SymEntry *currentEntry;
	struct SymEntry *newEntry;
	
	strcpy(n, Name);
	nameLength = strlen(n) + 1;
	
	if(ATable->Contents[hashValue] == NULL) {
		newEntry = (struct SymEntry*)malloc(sizeof(struct SymEntry*) + nameLength);
		newEntry->Name = n;
		newEntry->Next = NULL;
		ATable->Contents[hashValue] = newEntry;
		AnEntry = &newEntry;
		return false;
	} else {
		currentEntry = FindName(ATable, Name);[
		if(currentEntry != NULL) return true;
		/* else if( currentEntry == NULL )*/
		currentEntry = ATable->Contents[hashValue];
		while(currentEntry->Next !=NULL) {
			currentEntry = currentEntry->Next;
		}
		newEntry = (struct SymEntry*)malloc(sizeof(struct SymEntry*) + nameLength);
		newEntry->Name = n;
		newEntry->Next = NULL;
		currentEntry->Next = newEntry;
	}
		
};

and here's the method I'm trying to use for the assignment, line 158 highlighted.

struct SymEntry* FindName(struct SymTab *ATable,
                           const char * Name) {
		int comp;
		int hashValue = hash(Name,ATable);
		char n[200];
		int nameLength;
		struct SymEntry *currentEntry;
		
		strcpy(n, Name);
		nameLength = strlen(n) + 1;
		
		if(ATable->Contents[hashValue] == NULL){
			return NULL;
		} /*else */
		for(currentEntry = ATable->Contents[hashValue]; 
			currentEntry->Next != NULL; currentEntry = currentEntry->Next) {
			comp = strcmp( n, currentEntry->Name);
			if (comp == 0){
				return currentEntry;
			}
		}
		return NULL; /* wasn't found in the list at the hash value */
};

I know it's a lot of debugging to ask, but I'm really stumped at this point after going through this code.

[Elysia]

You forgot to add a prototype for FindName, so the compiler assumes it's declared as
int FindName();
(Note the missing void too.)
Make a prototype and put it into the header or stuff it at the top and the problem shall be solved.

[vart]

why your function bodies are in the header file?

your FindName function has no prototype before it is called. So compiler supposes that this function is
int FindName() - returns int - that's why you have your first warning

[P3nGu1N]

do you mean something like this before the method?

struct SymEntry * FindName(struct SymTab *ATable,
                           const char * Name);

or, what do you mean by 'prototype'?

[Elysia]

Yes, that's right.

[P3nGu1N]

Alright, put it at the top of my SymTab.h and got a clean compile.

Okay, so now I'm really confused why my other methods all compiled, but not this one without a prototype.
Should I have prototypes for all my other methods?

[Elysia]

There are two parts with every function: declaration and definition. A prototype is a declaration. A function which contains actual code is a definition, and a definition is also a declaration.
The compiler must have a declaration of the function you are trying to call before doing the call or it will assume an implicit function declaration (as we stated above).
So if a function comes before the function that calls it, it works, because the definition of the function is also a declaration, so the compiler knows of it.
That's why it worked.

For good practice, it is recommended you use prototypes for each of your functions.

[matsp]

Alright, put it at the top of my SymTab.h and got a clean compile.

Okay, so now I'm really confused why my other methods all compiled, but not this one without a prototype.
Should I have prototypes for all my other methods?

You need prototypes for functions that haven't been defined when they are being called - and being VERY technical, you only need it if you have functions that do not return integer. But it is always best to declare a prototype for ALL functions.

You also should not put function definitions in a header file.

--
Mats

[P3nGu1N]

You need prototypes for functions that haven't been defined when they are being called - and being VERY technical, you only need it if you have functions that do not return integer. But it is always best to declare a prototype for ALL functions.

You also should not put function definitions in a header file.

--
Mats

but the .c file is the driver my professor gave me. I assumed he wanted all of the coding done in the .h file.

Thanks for the explanation, it makes sense that it has to be declared before use.

[matsp]

You PROBABLY should create a second .c file, that contains the implementation of the functions. If you have functions in headers [that are not marked inline or static], then if you use the same header file in two places, you will get "multiple declaration" errors in linking, because you have two functions of the same name - which is not allowed.

--
Mats

[P3nGu1N]

Re-read my assignment sheet, and it does seem to want all coding in a separate SymTab.c file. I duplicated my folder, just in case something bad happened when I transferred all the methods over, but it went fairly smoothly.

I did, however, try to add the following prototypes to SymTab.h after making the big transfer, and it won't compile with them there:

int countEntries(struct SymTab *ATable);
int hash(char *s, struct SymTab *ATable);

I know I don't need them, but just out of pure curiosity, why won't it compile with these in my header?

Compiler Errors:
SymTab.c: In function 'EnterName':
SymTab.c:79: warning: passing argument 1 of 'hash' discards qualifiers from pointer target type
SymTab.c: In function 'FindName':
SymTab.c:120: warning: passing argument 1 of 'hash' discards qualifiers from pointer target type
SymTab.c: In function 'countEntries':
SymTab.c:217: error: number of arguments doesn't match prototype
SymTab.h:99: error: prototype declaration

[matsp]

Perhaps hash() should take a const char argument - after all, you aren't changing the string passed in, I guess?

And the other error is that countEntries takes one argument, and you are not giving it one argumet (you either give it more than one, or zero arguments).

--
Mats