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NED
Beta
Novice Errors Detection for C Programs

Start using NED now!

By using NED, you certify that you read, understood & agreed to the terms of usage.

Option #1 - Select files to upload

Use the file-browser below to select, one by one, all the .c or .h files in your project. Leave empty browsers if you do not need to analyze this many files. When you use the "Analyze" button, your files will be uploaded & analyzed. A new tab will open in your browser with a full report on possible errors.


Option #2 - Drag and Drop the files to upload

You might alternatively select a bunch of files in your file browser then drag and drop them here...

Drop Files Here to Upload

Option #3 - Upload a zip of your projet

You may alternatively zip your entire project folder then select the resulting zip file to upload


Things to keep in mind

This web app has been developed for Firefox. You may download a portable firefox version if you do not want to fully install it on your system. It should work on other standards-adhering browsing

Keep in mind these are potential errors, things you should take another look at in order to make sure they are not mistakes. Unfortunately, there is so much a program may do to understand another program.

Do not hesitate to drop us feedback, see about details here. If you want to learn a bit more about this project read here

Search through our tutorials

This table lists all our tutorials so you may peruse through them. The number of views for each is also displayed; this is not the number of times the error occured in an uploaded set of files but rather the number of times a user clicked on the messages hyperlinked to this tutorial in order to read it.

Similarly, the usefulness is based on the number of users who clicked yes at the bottom of a tutorial page. The uselessness is based on the number of those who clicked no.

The Freq. value represents how often the errors or warnings which the tutorial explains have been found during uploaded files analysis. It is a good estimate of the frequency of the underlying bugs among all NED users

Do not hesitate to use the mini-survey feature which you will find in the last section of each tutorial page. It helps identify both the tutorials in need of improvement but also those we should use as models.

Name From Type Details Views Useful Useless Freq.
Unused VariablesCompilerWarningVariable declared, maybe even assigned, but never used393011621
Undeclared VariablesCompilerErrorUndeclared variable used38222418
Undefined ReferencesLinkerErrorUndefined reference to function or variable38411
Missing Return StatementAnalyzerWarningFunction is missing return statement37510109
Missing Array SizeCompilerErrorThe size of an array is not specified3591166
Empty BlockAnalyzerWarningYour program features an empty block37112219
Single Quote StringCompilerWarningUsing single quote as string delimiter3785399
Unexpected Break StatementAnalyzerWarningUnexpected break statement3730064
Missing break statementAnalyzerWarningMissing break statement36283
Unreachable StatementsAnalyzerWarningUnreachable statements38217134
= vs. ==CompilerWarningAssignment used in Boolean expression42321393
Unary OPs in Larger ExprAnalyzerWarningUnary operators used in larger expression38000362
Bitwise vs. LogicalAnalyzerWarningUse of bitwise binary operator instead of logical operator37801284
Expected SemicolonCompilerErrorExpected semi-colon3702168
Dangling PointerAnalyzerWarningDangling pointer36631126
Dereferencing NULLAnalyzerWarningDereferencing NULL pointer3972562
Dereferencing Incomplete TypesCompilerErrorDereferencing a pointer to an incomplete data type36833421
Multi-free on same memory blockAnalyzerWarningFreeing multiple times the same memory block3770166
Memory LeakAnalyzerWarningMemory leak38004180
Freeing unallocated pointerAnalyzerWarningFreeing non-allocated memory37422141
sizeof on PointerAnalyzerWarningUsing sizeof operator on pointer37512
Uninitialized PointersAnalyzerWarningUnitialized pointer34516
Discarding Ptrs QualifiersCompilerWarningAssignment or cast discards pointers qualifier37611
Unchecked MallocAnalyzerWarningReturn value from malloc or similar function is not checked37201355
Unexpected EOFCompilerErrorUnexpected EOF3783374
Unterminated literalCompilerErrorMissing end-delimiter for character or string literal36021462
Useless ValueAnalyzerWarningStatement results in a value which is never used37731654
Void not IgnoredCompilerErrorAttempting to use a void returned value3890682
Missing EOF NewlineCompilerWarningMissing newline at end of file35930
Multiple Unary Ops on VariableCompilerWarningUsing multiple unary operators on same variable in a single expression38803216
Empty Char LiteralCompilerErrorEmpty character literal3533273
Using Uninitialized VariableCompilerWarningVariable not initialized3812278
Forward Parameter DeclarationCompilerErrorParameter has a forward-declaration377031640
Unexpected Data TypesCompilerErrorUnexpected multiple data types where one is expected38503201
Unexpected Arguments NumberCompilerErrorUnexpected number of arguments36110140
Mismatch numbers for args / specifiersCompilerWarningThere is a mismatch between the number of format specifiers used in a printf or scanf, and their arguments36121292
Mismatch types for args / specifiersCompilerWarningThere is a mismatch between the data type of format specifiers used in a printf or scanf, and the data type of the corresponding argument35822574
Using unknwon struct fieldCompilerErrorUnknown struct field37720138
Parameters Storage ClassCompilerErrorStorage class specified for parameter3532066
Shadowed IdentifierAnalyzerWarningShadowing variable already in scope3542148
Argument ConversionCompilerWarningArguments data type is converted36820447
Modifying ParametersAnalyzerWarningFormal parameters are assigned inside function36320137
Assign Integer to PointerCompilerWarningAssigning non-NULL constant to Pointer37901218
Mixed Pointers DeclarationsAnalyzerWarningDeclaring variables in one statement with pointer and non-pointer data types36020
Missing Function DeclarationCompilerWarningMissing function declaration36731
Function should not be exportedAnalyzerWarningFunction is not static to its file, yet unused in other files37930931
Off by oneAnalyzerWarningA loop might be off by one in its number of iteration; e.g. start at 0 instead of 13440039
Formatting String MismatchAnalyzerWarningA printf or scanf is using a formatting string with conversion specifiers unrelated to the parameters36501
Assign pointer to integerAnalyzerWarningAssigning memory address to variable expecting integer36900162
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