XS-Labs - Blog

Below is the complete list of the warning flags I use with Clang, the C frontend for LLVM.
I personally use those flags for all my production code, for C, C++ and Objective-C development.

Basically, all warning flags are activated. I had to look at the Clang source code to find all of them.

I also created a header file which automatically sets those flags, when compiling source code.
This way, whether you use an IDE or command-line to compile your code, you won’t need anymore to set those flags, as long as you include the header.
It’s available here on GitHub. Enjoy!

Warning flags list:

• -Wabi
• -Waddress-of-temporary
• -Waddress
• -Waggregate-return
• -Wall
• -Wambiguous-member-template
• -Warc-abi
• -Warc-non-pod-memaccess
• -Warc-retain-cycles
• -Warc-unsafe-retained-assign
• -Warc
• -Watomic-properties
• -Wattributes
• -Wavailability
• -Wbad-function-cast
• -Wbind-to-temporary-copy
• -Wbitwise-op-parentheses
• -Wbool-conversions
• -Wbuiltin-macro-redefined
• -Wc++-compat
• -Wc++0x-compat
• -Wc++0x-extensions
• -Wcast-align
• -Wcast-qual
• -Wchar-align
• -Wchar-subscripts
• -Wcomment
• -Wcomments
• -Wconditional-uninitialized
• -Wconversion
• -Wctor-dtor-privacy
• -Wcustom-atomic-properties
• -Wdeclaration-after-statement
• -Wdefault-arg-special-member
• -Wdelegating-ctor-cycles
• -Wdelete-non-virtual-dtor
• -Wdeprecated-declarations
• -Wdeprecated-implementations
• -Wdeprecated-writable-strings
• -Wdeprecated
• -Wdisabled-optimization
• -Wdiscard-qual
• -Wdiv-by-zero
• -Wduplicate-method-arg
• -Weffc++
• -Wempty-body
• -Wendif-labels
• -Wexit-time-destructors
• -Wextra-tokens
• -Wextra
• -Wformat-extra-args
• -Wformat-nonliteral
• -Wformat-zero-length
• -Wformat
• -Wformat=2
• -Wfour-char-constants
• -Wglobal-constructors
• -Wgnu-designator
• -Wgnu
• -Wheader-hygiene
• -Widiomatic-parentheses
• -Wignored-qualifiers
• -Wimplicit-atomic-properties
• -Wimplicit-function-declaration
• -Wimplicit-int
• -Wimplicit
• -Wimport
• -Wincompatible-pointer-types
• -Winit-self
• -Winitializer-overrides
• -Winline
• -Wint-to-pointer-cast
• -Winvalid-offsetof
• -Winvalid-pch
• -Wlarge-by-value-copy
• -Wliteral-range
• -Wlocal-type-template-args
• -Wlogical-op-parentheses
• -Wlong-long
• -Wmain
• -Wmicrosoft
• -Wmismatched-tags
• -Wmissing-braces
• -Wmissing-declarations
• -Wmissing-field-initializers
• -Wmissing-format-attribute
• -Wmissing-include-dirs
• -Wmissing-noreturn
• -Wmost
• -Wmultichar
• -Wnested-externs
• -Wnewline-eof
• -Wnon-gcc
• -Wnon-virtual-dtor
• -Wnonfragile-abi2
• -Wnonnull
• -Wnonportable-cfstrings
• -Wnull-dereference
• -Wobjc-nonunified-exceptions
• -Wold-style-cast
• -Wold-style-definition
• -Wout-of-line-declaration
• -Woverflow
• -Woverlength-strings
• -Woverloaded-virtual
• -Wpacked
• -Wpadded
• -Wparentheses
• -Wpointer-arith
• -Wpointer-to-int-cast
• -Wprotocol
• -Wreadonly-setter-attrs
• -Wredundant-decls
• -Wreorder
• -Wreturn-type
• -Wself-assign
• -Wsemicolon-before-method-body
• -Wsequence-point
• -Wshadow
• -Wshorten-64-to-32
• -Wsign-compare
• -Wsign-promo
• -Wsizeof-array-argument
• -Wstack-protector
• -Wstrict-aliasing
• -Wstrict-overflow
• -Wstrict-prototypes
• -Wstrict-selector-match
• -Wsuper-class-method-mismatch
• -Wswitch-default
• -Wswitch-enum
• -Wswitch
• -Wsynth
• -Wtautological-compare
• -Wtrigraphs
• -Wtype-limits
• -Wundeclared-selector
• -Wuninitialized
• -Wunknown-pragmas
• -Wunnamed-type-template-args
• -Wunneeded-internal-declaration
• -Wunneeded-member-function
• -Wunused-argument
• -Wunused-exception-parameter
• -Wunused-function
• -Wunused-label
• -Wunused-member-function
• -Wunused-parameter
• -Wunused-value
• -Wunused-variable
• -Wunused
• -Wused-but-marked-unused
• -Wvariadic-macros
• -Wvector-conversions
• -Wvla
• -Wvolatile-register-var
• -Wwrite-strings