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@johnsogg
Created January 25, 2013 21:49
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seg fault is somewhere
void remove(node** parent, int offset) {
node* cursor = *parent;
if (cursor->next==NULL || offset > size(*parent)) {
return;
} else if (offset==0) {
cursor=cursor->next;
} else {
for (int i=1;i<offset;i++) {
cursor=cursor->next;
}
cursor->next=cursor->next->next;
}
}
@johnsogg
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Author

well,
*cursor is a node.
but,
cursor is a node*
cursor->next is also a node*

There are a bunch of syntax errors in the above, so I assume you didn't paste in literally what you have.

At any rate, if cursor (the node pointer) is null, then calling cursor->next will segfault.

Paste in the RG output.

@coaw8679
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Created a RetroGrade instance.
Assignment: hw_1_linked_lists
Student: connor.awe@colorado.edu
Student Files: /tmp/tmpsHfsFt/linked_list.cpp
File: /tmp/tmpsHfsFt/linked_list.cpp
Determined language = cpp
About to copy files to working directory: /tmp/tmpVxLqvb
Copying Student files...
... /tmp/tmpsHfsFt/linked_list.cpp
Copied Student files.
Copying Instructor files...
... linked_list.h
... description.json
... linked_list_test.cpp
... RetroPrinter.h
... Makefile
... RetroPrinter.cpp
Copied Instructor files.
Copy files successful
Invoking grade script
Changing directory to /tmp/tmpVxLqvb
... successfully changed directory.
Using description files: /home/gabe/grading-scripts/hw_1_linked_lists/description-common.json /home/gabe/grading-scripts/hw_1_linked_lists/cpp/description.json
... got assignment instance.
Invoking grade()...
Description File: /home/gabe/grading-scripts/hw_1_linked_lists/description-common.json
Description File: /home/gabe/grading-scripts/hw_1_linked_lists/cpp/description.json
Assignment: Linked Lists
Language: cpp
Points Possible: 15
Instructor file(s) in place.
Student file(s) in place.

Running Build command: make...
... return value: True

g++ -I/usr/local/gtest-1.6.0/include -g -Wall -Wextra -c ./linked_list.cpp
g++ -I/usr/local/gtest-1.6.0/include -g -Wall -Wextra -c ./linked_list_test.cpp
g++ -I/usr/local/gtest-1.6.0/include -g -Wall -Wextra -c ./RetroPrinter.cpp
g++ -I/usr/local/gtest-1.6.0/include -g -Wall -Wextra -pthread linked_list.o linked_list_test.o RetroPrinter.o /usr/local/gtest-1.6.0/make/gtest_main.a -o linked_list_test

Running Unit Test command: ./linked_list_test...
... return value: False

Segmentation fault

Parsing outfile...
Checking for ommitted tests


  • WARNING: Tests performed were not the same as those prescribed.
  • missing: Contains
  • missing: Size

Completed unit test command.
result: {'Insert': (3, 3), 'InitNode': (1, 1), 'InsertData': (1, 1), 'Remove': (0, 3), 'Report': (2, 2), 'AppendData': (1, 1), 'Append': (2, 2)}
errors: FYI: should be 4, 30, 20, 10: 4 30 20 10
FYI: should be 4, 30, -8, 20, 10: 4 30 -8 20 10
FYI: should be 4, 30, -8, 20, 10, 99: 4 30 -8 20 10 99
FYI: should be 5, 7, 98, -34: 5 7 98 -34
FYI: should be 5, 7, 20, 98, -34: 5 7 20 98 -34
FYI: should be 5, 7, 20, 98, -34, 800: 5 7 20 98 -34 800
7 != 86
Failure at ./linked_list_test.cpp:198:
Value of: expect_all(vals2, 2, &top)
Actual: false
Expected: true

Done reporting result and errors.
FYI: should be 4, 30, 20, 10: 4 30 20 10
FYI: should be 4, 30, -8, 20, 10: 4 30 -8 20 10
FYI: should be 4, 30, -8, 20, 10, 99: 4 30 -8 20 10 99
FYI: should be 5, 7, 98, -34: 5 7 98 -34
FYI: should be 5, 7, 20, 98, -34: 5 7 20 98 -34
FYI: should be 5, 7, 20, 98, -34, 800: 5 7 20 98 -34 800
7 != 86
Failure at ./linked_list_test.cpp:198:
Value of: expect_all(vals2, 2, &top)
Actual: false
Expected: true

Output is in the file: /tmp/tmpVxLqvb/unit_test_output.txt

@coaw8679
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It gives the same message even when I comment out everything in the remove function (except the brackets so that the driver will run).

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