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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 used406011725
Undeclared VariablesCompilerErrorUndeclared variable used39522451
Undefined ReferencesLinkerErrorUndefined reference to function or variable38811
Missing Return StatementAnalyzerWarningFunction is missing return statement38110127
Missing Array SizeCompilerErrorThe size of an array is not specified3661171
Empty BlockAnalyzerWarningYour program features an empty block38412226
Single Quote StringCompilerWarningUsing single quote as string delimiter38253102
Unexpected Break StatementAnalyzerWarningUnexpected break statement3780067
Missing break statementAnalyzerWarningMissing break statement37283
Unreachable StatementsAnalyzerWarningUnreachable statements39217140
= vs. ==CompilerWarningAssignment used in Boolean expression42721417
Unary OPs in Larger ExprAnalyzerWarningUnary operators used in larger expression38700386
Bitwise vs. LogicalAnalyzerWarningUse of bitwise binary operator instead of logical operator38601297
Expected SemicolonCompilerErrorExpected semi-colon3822172
Dangling PointerAnalyzerWarningDangling pointer37731133
Dereferencing NULLAnalyzerWarningDereferencing NULL pointer4072574
Dereferencing Incomplete TypesCompilerErrorDereferencing a pointer to an incomplete data type37433442
Multi-free on same memory blockAnalyzerWarningFreeing multiple times the same memory block3850169
Memory LeakAnalyzerWarningMemory leak38904195
Freeing unallocated pointerAnalyzerWarningFreeing non-allocated memory38222144
sizeof on PointerAnalyzerWarningUsing sizeof operator on pointer38012
Uninitialized PointersAnalyzerWarningUnitialized pointer35416
Discarding Ptrs QualifiersCompilerWarningAssignment or cast discards pointers qualifier38411
Unchecked MallocAnalyzerWarningReturn value from malloc or similar function is not checked38301381
Unexpected EOFCompilerErrorUnexpected EOF3853379
Unterminated literalCompilerErrorMissing end-delimiter for character or string literal38321490
Useless ValueAnalyzerWarningStatement results in a value which is never used38331665
Void not IgnoredCompilerErrorAttempting to use a void returned value4000686
Missing EOF NewlineCompilerWarningMissing newline at end of file36830
Multiple Unary Ops on VariableCompilerWarningUsing multiple unary operators on same variable in a single expression39403234
Empty Char LiteralCompilerErrorEmpty character literal3583275
Using Uninitialized VariableCompilerWarningVariable not initialized3942284
Forward Parameter DeclarationCompilerErrorParameter has a forward-declaration383031652
Unexpected Data TypesCompilerErrorUnexpected multiple data types where one is expected39103216
Unexpected Arguments NumberCompilerErrorUnexpected number of arguments36810152
Mismatch numbers for args / specifiersCompilerWarningThere is a mismatch between the number of format specifiers used in a printf or scanf, and their arguments36721310
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 argument37022582
Using unknwon struct fieldCompilerErrorUnknown struct field38620154
Parameters Storage ClassCompilerErrorStorage class specified for parameter3622080
Shadowed IdentifierAnalyzerWarningShadowing variable already in scope3592151
Argument ConversionCompilerWarningArguments data type is converted37620462
Modifying ParametersAnalyzerWarningFormal parameters are assigned inside function36820147
Assign Integer to PointerCompilerWarningAssigning non-NULL constant to Pointer38601227
Mixed Pointers DeclarationsAnalyzerWarningDeclaring variables in one statement with pointer and non-pointer data types36720
Missing Function DeclarationCompilerWarningMissing function declaration37331
Function should not be exportedAnalyzerWarningFunction is not static to its file, yet unused in other files386301012
Off by oneAnalyzerWarningA loop might be off by one in its number of iteration; e.g. start at 0 instead of 13530041
Formatting String MismatchAnalyzerWarningA printf or scanf is using a formatting string with conversion specifiers unrelated to the parameters37101
Assign pointer to integerAnalyzerWarningAssigning memory address to variable expecting integer37300166
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