insert - Keep getting a seg fault with my binary search (working in C) -

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i'm having trouble getting binary tree work. 1 weird thing when try print node data repeatedly, seg fault. i'm taking red flag i'm doing wrong. test program made struct definition , insertion function. notice issue?

   #include <stdio.h>     #include <stdlib.h>     #include <assert.h>     #include <string.h>     #include <stdbool.h>       typedef struct tnode{          char *name;         int value;          struct tnode *left;         struct tnode *right;      } tnode;       tnode *insert(tnode *node, char *name, int value){           if(node==null){              tnode *temp = malloc(sizeof(struct tnode));              temp->name = strdup(name);             temp->value = value;              temp->left = null;             temp->right = null;              return temp;          }          else if(strcmp(name,node->name)<0)         {             node->left = insert(node->left, name, value);            }          else if(strcmp(name,node->name)>0)         {             node->right = insert(node->right, name, value);         }            else{             printf("something went wrong\n");         }         }       int main(){          tnode *root = null;          root = insert(root,"george",11);         root = insert(root,"dick",12);         root = insert(root,"walter",13);         root = insert(root,"harry",13);         printf("%s\n",root->name);           root = insert(root,"zink",40);         printf("%s\n",root->name);        }

the "insert" function not return anything, except in first if (node==null) case. when you're not returning function supposed return value, behavior undefined; may segfault, or may appear run on else's system, etc.

for cases besides if (node==null) case, want return node;. or, may want abort() or exit() or in "something went wrong" case. should return 0; main, that's not causing problem.

these issues easier notice if compile warnings turned on. compilers (e.g. gcc), can turn on many warnings passing -wall flag compiler. recommend compiling @ least -wall.


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