Properties, C/C++ Settings, Tools Settings, Warnings

Set the warnings settings

Option Description
Other flags Other warning flags
Check syntax only (-fsyntax-only) Check the code for syntax errors, but don’t do anything beyond that.
Pedantic (-pedantic) Issue all the warnings demanded by strict ISO C and ISO C++; reject all programs that use forbidden extensions, and some other programs that do not follow ISO C and ISO C++. For ISO C, follows the version of the ISO C standard specified by any ‘-std’ option used.
Pedantic warnings as errors (-pedantic-errors) Like -pedantic, except that errors are produced rather than warnings.
Inhibit all warnings (-w) Inhibit all warning messages. Not recommended.
Enable all common warnings (-Wall) Enable all the warnings about constructions that some users consider questionable, and that are easy to avoid (or modify to prevent the warning), even in conjunction with macros. This also enables some language-specific warnings.
Enable extra warnings(-Wextra) Enable some extra warning flags that are not enabled by -Wall.
Make all warnings into errors (-Werror) Make all warnings into errors.
Warn on implicit conversions (-Wconversion) Warn for implicit conversions that may alter a value. This includes conversions between real and integer, like abs (x) when x is double; conversions between signed and unsigned, like unsigned ui = -1; and conversions to smaller types, like sqrtf (M_PI). Do not warn for explicit casts like abs ((int) x) and ui = (unsigned) -1, or if the value is not changed by the conversion like in abs (2.0). Warnings about conversions between signed and unsigned integers can be disabled by using ‘-Wno-sign-conversion’.
Warn on various unused elements (-Wunused) Warn if various constructs are unused (parameters, functions, labels, etc).