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GNU Info File | 2001-07-15 | 34.6 KB | 852 lines

This is Info file gcc.info, produced by Makeinfo version 1.68 from the input file ./gcc.texi. INFO-DIR-SECTION Programming START-INFO-DIR-ENTRY * gcc: (gcc). The GNU Compiler Collection. END-INFO-DIR-ENTRY This file documents the use and the internals of the GNU compiler. Published by the Free Software Foundation 59 Temple Place - Suite 330 Boston, MA 02111-1307 USA Copyright (C) 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc. Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided also that the sections entitled "GNU General Public License" and "Funding for Free Software" are included exactly as in the original, and provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Permission is granted to copy and distribute translations of this manual into another language, under the above conditions for modified versions, except that the sections entitled "GNU General Public License" and "Funding for Free Software", and this permission notice, may be included in translations approved by the Free Software Foundation instead of in the original English. File: gcc.info, Node: C++ Dialect Options, Next: Warning Options, Prev: C Dialect Options, Up: Invoking GCC Options Controlling C++ Dialect =============================== This section describes the command-line options that are only meaningful for C++ programs; but you can also use most of the GNU compiler options regardless of what language your program is in. For example, you might compile a file `firstClass.C' like this: g++ -g -frepo -O -c firstClass.C In this example, only `-frepo' is an option meant only for C++ programs; you can use the other options with any language supported by GCC. Here is a list of options that are *only* for compiling C++ programs: `-fno-access-control' Turn off all access checking. This switch is mainly useful for working around bugs in the access control code. `-fcheck-new' Check that the pointer returned by `operator new' is non-null before attempting to modify the storage allocated. The current Working Paper requires that `operator new' never return a null pointer, so this check is normally unnecessary. An alternative to using this option is to specify that your `operator new' does not throw any exceptions; if you declare it `throw()', g++ will check the return value. See also `new (nothrow)'. `-fconserve-space' Put uninitialized or runtime-initialized global variables into the common segment, as C does. This saves space in the executable at the cost of not diagnosing duplicate definitions. If you compile with this flag and your program mysteriously crashes after `main()' has completed, you may have an object that is being destroyed twice because two definitions were merged. This option is no longer useful on most targets, now that support has been added for putting variables into BSS without making them common. `-fdollars-in-identifiers' Accept `$' in identifiers. You can also explicitly prohibit use of `$' with the option `-fno-dollars-in-identifiers'. (GNU C allows `$' by default on most target systems, but there are a few exceptions.) Traditional C allowed the character `$' to form part of identifiers. However, ANSI C and C++ forbid `$' in identifiers. `-fno-elide-constructors' The C++ standard allows an implementation to omit creating a temporary which is only used to initialize another object of the same type. Specifying this option disables that optimization, and forces g++ to call the copy constructor in all cases. `-fexternal-templates' Cause template instantiations to obey `#pragma interface' and `implementation'; template instances are emitted or not according to the location of the template definition. *Note Template Instantiation::, for more information. This option is deprecated. `-falt-external-templates' Similar to -fexternal-templates, but template instances are emitted or not according to the place where they are first instantiated. *Note Template Instantiation::, for more information. This option is deprecated. `-ffor-scope' `-fno-for-scope' If -ffor-scope is specified, the scope of variables declared in a for-init-statement is limited to the `for' loop itself, as specified by the draft C++ standard. If -fno-for-scope is specified, the scope of variables declared in a for-init-statement extends to the end of the enclosing scope, as was the case in old versions of gcc, and other (traditional) implementations of C++. The default if neither flag is given to follow the standard, but to allow and give a warning for old-style code that would otherwise be invalid, or have different behavior. `-fno-gnu-keywords' Do not recognize `classof', `headof', `signature', `sigof' or `typeof' as a keyword, so that code can use these words as identifiers. You can use the keywords `__classof__', `__headof__', `__signature__', `__sigof__', and `__typeof__' instead. `-ansi' implies `-fno-gnu-keywords'. `-fguiding-decls' Treat a function declaration with the same type as a potential function template instantiation as though it declares that instantiation, not a normal function. If a definition is given for the function later in the translation unit (or another translation unit if the target supports weak symbols), that definition will be used; otherwise the template will be instantiated. This behavior reflects the C++ language prior to September 1996, when guiding declarations were removed. This option implies `-fname-mangling-version-0', and will not work with other name mangling versions. Like all options that change the ABI, all C++ code, *including libgcc.a* must be built with the same setting of this option. `-fhandle-signatures' Recognize the `signature' and `sigof' keywords for specifying abstract types. The default (`-fno-handle-signatures') is not to recognize them. *Note Type Abstraction using Signatures: C++ Signatures. `-fhonor-std' Treat the `namespace std' as a namespace, instead of ignoring it. For compatibility with earlier versions of g++, the compiler will, by default, ignore `namespace-declarations', `using-declarations', `using-directives', and `namespace-names', if they involve `std'. `-fhuge-objects' Support virtual function calls for objects that exceed the size representable by a `short int'. Users should not use this flag by default; if you need to use it, the compiler will tell you so. This flag is not useful when compiling with -fvtable-thunks. Like all options that change the ABI, all C++ code, *including libgcc* must be built with the same setting of this option. `-fno-implicit-templates' Never emit code for non-inline templates which are instantiated implicitly (i.e. by use); only emit code for explicit instantiations. *Note Template Instantiation::, for more information. `-fno-implicit-inline-templates' Don't emit code for implicit instantiations of inline templates, either. The default is to handle inlines differently so that compiles with and without optimization will need the same set of explicit instantiations. `-finit-priority' Support `__attribute__ ((init_priority (n)))' for controlling the order of initialization of file-scope objects. On ELF targets, this requires GNU ld 2.10 or later. `-fno-implement-inlines' To save space, do not emit out-of-line copies of inline functions controlled by `#pragma implementation'. This will cause linker errors if these functions are not inlined everywhere they are called. `-fname-mangling-version-N' Control the way in which names are mangled. Version 0 is compatible with versions of g++ before 2.8. Version 1 is the default. Version 1 will allow correct mangling of function templates. For example, version 0 mangling does not mangle foo<int, double> and foo<int, char> given this declaration: template <class T, class U> void foo(T t); Like all options that change the ABI, all C++ code, *including libgcc* must be built with the same setting of this option. `-foperator-names' Recognize the operator name keywords `and', `bitand', `bitor', `compl', `not', `or' and `xor' as synonyms for the symbols they refer to. `-ansi' implies `-foperator-names'. `-fno-optional-diags' Disable diagnostics that the standard says a compiler does not need to issue. Currently, the only such diagnostic issued by g++ is the one for a name having multiple meanings within a class. `-fpermissive' Downgrade messages about nonconformant code from errors to warnings. By default, g++ effectively sets `-pedantic-errors' without `-pedantic'; this option reverses that. This behavior and this option are superceded by `-pedantic', which works as it does for GNU C. `-frepo' Enable automatic template instantiation. This option also implies `-fno-implicit-templates'. *Note Template Instantiation::, for more information. `-fno-rtti' Disable generation of the information used by C++ runtime type identification features (`dynamic_cast' and `typeid'). If you don't use those parts of the language (or exception handling, which uses `dynamic_cast' internally), you can save some space by using this flag. `-fstrict-prototype' Within an `extern "C"' linkage specification, treat a function declaration with no arguments, such as `int foo ();', as declaring the function to take no arguments. Normally, such a declaration means that the function `foo' can take any combination of arguments, as in C. `-pedantic' implies `-fstrict-prototype' unless overridden with `-fno-strict-prototype'. Specifying this option will also suppress implicit declarations of functions. This flag no longer affects declarations with C++ linkage. `-fsquangle' `-fno-squangle' `-fsquangle' will enable a compressed form of name mangling for identifiers. In particular, it helps to shorten very long names by recognizing types and class names which occur more than once, replacing them with special short ID codes. This option also requires any C++ libraries being used to be compiled with this option as well. The compiler has this disabled (the equivalent of `-fno-squangle') by default. Like all options that change the ABI, all C++ code, *including libgcc.a* must be built with the same setting of this option. `-ftemplate-depth-N' Set the maximum instantiation depth for template classes to N. A limit on the template instantiation depth is needed to detect endless recursions during template class instantiation. ANSI/ISO C++ conforming programs must not rely on a maximum depth greater than 17. `-fthis-is-variable' Permit assignment to `this'. The incorporation of user-defined free store management into C++ has made assignment to `this' an anachronism. Therefore, by default it is invalid to assign to `this' within a class member function; that is, GNU C++ treats `this' in a member function of class `X' as a non-lvalue of type `X *'. However, for backwards compatibility, you can make it valid with `-fthis-is-variable'. `-fvtable-thunks=THUNKS-VERSION' Use `thunks' to implement the virtual function dispatch table (`vtable'). The traditional (cfront-style) approach to implementing vtables was to store a pointer to the function and two offsets for adjusting the `this' pointer at the call site. Newer implementations store a single pointer to a `thunk' function which does any necessary adjustment and then calls the target function. The original implementation of thunks (version 1) had a bug regarding virtual base classes; this bug is fixed with version 2 of the thunks implementation. With setting the version to 2, compatibility to the version 1 thunks is provided, at the cost of extra machine code. Version 3 does not include this compatibility. This option also enables a heuristic for controlling emission of vtables; if a class has any non-inline virtual functions, the vtable will be emitted in the translation unit containing the first one of those. Like all options that change the ABI, all C++ code, *including libgcc.a* must be built with the same setting of this option. Since version 1 and version 2 are also incompatible (for classes with virtual bases defining virtual functions), all code must also be compiled with the same version. In this version of gcc, there are no targets for which version 2 thunks are the default. On all targets, not giving the option will use the traditional implementation, and -fvtable-thunks will produce version 2 thunks. `-nostdinc++' Do not search for header files in the standard directories specific to C++, but do still search the other standard directories. (This option is used when building the C++ library.) In addition, these optimization, warning, and code generation options have meanings only for C++ programs: `-fno-default-inline' Do not assume `inline' for functions defined inside a class scope. *Note Options That Control Optimization: Optimize Options. Note that these functions will have linkage like inline functions; they just won't be inlined by default. `-Wctor-dtor-privacy (C++ only)' Warn when a class seems unusable, because all the constructors or destructors in a class are private and the class has no friends or public static member functions. `-Wnon-virtual-dtor (C++ only)' Warn when a class declares a non-virtual destructor that should probably be virtual, because it looks like the class will be used polymorphically. `-Wreorder (C++ only)' Warn when the order of member initializers given in the code does not match the order in which they must be executed. For instance: struct A { int i; int j; A(): j (0), i (1) { } }; Here the compiler will warn that the member initializers for `i' and `j' will be rearranged to match the declaration order of the members. The following `-W...' options are not affected by `-Wall'. `-Weffc++ (C++ only)' Warn about violations of various style guidelines from Scott Meyers' `Effective C++' books. If you use this option, you should be aware that the standard library headers do not obey all of these guidelines; you can use `grep -v' to filter out those warnings. `-Wno-deprecated (C++ only)' Do not warn about usage of deprecated features. *Note Deprecated Features::. `-Wno-non-template-friend (C++ only)' Disable warnings when non-templatized friend functions are declared within a template. With the advent of explicit template specification support in g++, if the name of the friend is an unqualified-id (ie, `friend foo(int)'), the C++ language specification demands that the friend declare or define an ordinary, nontemplate function. (Section 14.5.3). Before g++ implemented explicit specification, unqualified-ids could be interpreted as a particular specialization of a templatized function. Because this non-conforming behavior is no longer the default behavior for g++, `-Wnon-template-friend' allows the compiler to check existing code for potential trouble spots, and is on by default. This new compiler behavior can also be turned off with the flag `-fguiding-decls', which activates the older, non-specification compiler code, or with `-Wno-non-template-friend' which keeps the conformant compiler code but disables the helpful warning. `-Wold-style-cast (C++ only)' Warn if an old-style (C-style) cast is used within a C++ program. The new-style casts (`static_cast', `reinterpret_cast', and `const_cast') are less vulnerable to unintended effects. `-Woverloaded-virtual (C++ only)' Warn when a derived class function declaration may be an error in defining a virtual function. In a derived class, the definitions of virtual functions must match the type signature of a virtual function declared in the base class. With this option, the compiler warns when you define a function with the same name as a virtual function, but with a type signature that does not match any declarations from the base class. `-Wno-pmf-conversions (C++ only)' Disable the diagnostic for converting a bound pointer to member function to a plain pointer. `-Wsign-promo (C++ only)' Warn when overload resolution chooses a promotion from unsigned or enumeral type to a signed type over a conversion to an unsigned type of the same size. Previous versions of g++ would try to preserve unsignedness, but the standard mandates the current behavior. `-Wsynth (C++ only)' Warn when g++'s synthesis behavior does not match that of cfront. For instance: struct A { operator int (); A& operator = (int); }; main () { A a,b; a = b; } In this example, g++ will synthesize a default `A& operator = (const A&);', while cfront will use the user-defined `operator ='. File: gcc.info, Node: Warning Options, Next: Debugging Options, Prev: C++ Dialect Options, Up: Invoking GCC Options to Request or Suppress Warnings ======================================= Warnings are diagnostic messages that report constructions which are not inherently erroneous but which are risky or suggest there may have been an error. You can request many specific warnings with options beginning `-W', for example `-Wimplicit' to request warnings on implicit declarations. Each of these specific warning options also has a negative form beginning `-Wno-' to turn off warnings; for example, `-Wno-implicit'. This manual lists only one of the two forms, whichever is not the default. These options control the amount and kinds of warnings produced by GCC: `-fsyntax-only' Check the code for syntax errors, but don't do anything beyond that. `-pedantic' Issue all the warnings demanded by strict ANSI C and ISO C++; reject all programs that use forbidden extensions. Valid ANSI C and ISO C++ programs should compile properly with or without this option (though a rare few will require `-ansi'). However, without this option, certain GNU extensions and traditional C and C++ features are supported as well. With this option, they are rejected. `-pedantic' does not cause warning messages for use of the alternate keywords whose names begin and end with `__'. Pedantic warnings are also disabled in the expression that follows `__extension__'. However, only system header files should use these escape routes; application programs should avoid them. *Note Alternate Keywords::. This option is not intended to be useful; it exists only to satisfy pedants who would otherwise claim that GCC fails to support the ANSI standard. Some users try to use `-pedantic' to check programs for strict ANSI C conformance. They soon find that it does not do quite what they want: it finds some non-ANSI practices, but not all--only those for which ANSI C *requires* a diagnostic. A feature to report any failure to conform to ANSI C might be useful in some instances, but would require considerable additional work and would be quite different from `-pedantic'. We don't have plans to support such a feature in the near future. `-pedantic-errors' Like `-pedantic', except that errors are produced rather than warnings. `-w' Inhibit all warning messages. `-Wno-import' Inhibit warning messages about the use of `#import'. `-Wchar-subscripts' Warn if an array subscript has type `char'. This is a common cause of error, as programmers often forget that this type is signed on some machines. `-Wcomment' Warn whenever a comment-start sequence `/*' appears in a `/*' comment, or whenever a Backslash-Newline appears in a `//' comment. `-Wformat' Check calls to `printf' and `scanf', etc., to make sure that the arguments supplied have types appropriate to the format string specified. `-Wimplicit-int' Warn when a declaration does not specify a type. `-Wimplicit-function-declaration' `-Werror-implicit-function-declaration' Give a warning (or error) whenever a function is used before being declared. `-Wimplicit' Same as `-Wimplicit-int' and `-Wimplicit-function-' `declaration'. `-Wmain' Warn if the type of `main' is suspicious. `main' should be a function with external linkage, returning int, taking either zero arguments, two, or three arguments of appropriate types. `-Wmultichar' Warn if a multicharacter constant (`'FOOF'') is used. Usually they indicate a typo in the user's code, as they have implementation-defined values, and should not be used in portable code. `-Wparentheses' Warn if parentheses are omitted in certain contexts, such as when there is an assignment in a context where a truth value is expected, or when operators are nested whose precedence people often get confused about. Also warn about constructions where there may be confusion to which `if' statement an `else' branch belongs. Here is an example of such a case: { if (a) if (b) foo (); else bar (); } In C, every `else' branch belongs to the innermost possible `if' statement, which in this example is `if (b)'. This is often not what the programmer expected, as illustrated in the above example by indentation the programmer chose. When there is the potential for this confusion, GNU C will issue a warning when this flag is specified. To eliminate the warning, add explicit braces around the innermost `if' statement so there is no way the `else' could belong to the enclosing `if'. The resulting code would look like this: { if (a) { if (b) foo (); else bar (); } } `-Wreturn-type' Warn whenever a function is defined with a return-type that defaults to `int'. Also warn about any `return' statement with no return-value in a function whose return-type is not `void'. `-Wswitch' Warn whenever a `switch' statement has an index of enumeral type and lacks a `case' for one or more of the named codes of that enumeration. (The presence of a `default' label prevents this warning.) `case' labels outside the enumeration range also provoke warnings when this option is used. `-Wtrigraphs' Warn if any trigraphs are encountered (assuming they are enabled). `-Wunused' Warn whenever a variable is unused aside from its declaration, whenever a function is declared static but never defined, whenever a label is declared but not used, and whenever a statement computes a result that is explicitly not used. In order to get a warning about an unused function parameter, you must specify both `-W' and `-Wunused'. To suppress this warning for an expression, simply cast it to void. For unused variables, parameters and labels, use the `unused' attribute (*note Variable Attributes::.). `-Wuninitialized' An automatic variable is used without first being initialized. These warnings are possible only in optimizing compilation, because they require data flow information that is computed only when optimizing. If you don't specify `-O', you simply won't get these warnings. These warnings occur only for variables that are candidates for register allocation. Therefore, they do not occur for a variable that is declared `volatile', or whose address is taken, or whose size is other than 1, 2, 4 or 8 bytes. Also, they do not occur for structures, unions or arrays, even when they are in registers. Note that there may be no warning about a variable that is used only to compute a value that itself is never used, because such computations may be deleted by data flow analysis before the warnings are printed. These warnings are made optional because GCC is not smart enough to see all the reasons why the code might be correct despite appearing to have an error. Here is one example of how this can happen: { int x; switch (y) { case 1: x = 1; break; case 2: x = 4; break; case 3: x = 5; } foo (x); } If the value of `y' is always 1, 2 or 3, then `x' is always initialized, but GCC doesn't know this. Here is another common case: { int save_y; if (change_y) save_y = y, y = new_y; ... if (change_y) y = save_y; } This has no bug because `save_y' is used only if it is set. Some spurious warnings can be avoided if you declare all the functions you use that never return as `noreturn'. *Note Function Attributes::. `-Wunknown-pragmas' Warn when a #pragma directive is encountered which is not understood by GCC. If this command line option is used, warnings will even be issued for unknown pragmas in system header files. This is not the case if the warnings were only enabled by the `-Wall' command line option. `-Wall' All of the above `-W' options combined. This enables 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. The following `-W...' options are not implied by `-Wall'. Some of them warn about constructions that users generally do not consider questionable, but which occasionally you might wish to check for; others warn about constructions that are necessary or hard to avoid in some cases, and there is no simple way to modify the code to suppress the warning. `-W' Print extra warning messages for these events: * A nonvolatile automatic variable might be changed by a call to `longjmp'. These warnings as well are possible only in optimizing compilation. The compiler sees only the calls to `setjmp'. It cannot know where `longjmp' will be called; in fact, a signal handler could call it at any point in the code. As a result, you may get a warning even when there is in fact no problem because `longjmp' cannot in fact be called at the place which would cause a problem. * A function can return either with or without a value. (Falling off the end of the function body is considered returning without a value.) For example, this function would evoke such a warning: foo (a) { if (a > 0) return a; } * An expression-statement or the left-hand side of a comma expression contains no side effects. To suppress the warning, cast the unused expression to void. For example, an expression such as `x[i,j]' will cause a warning, but `x[(void)i,j]' will not. * An unsigned value is compared against zero with `<' or `<='. * A comparison like `x<=y<=z' appears; this is equivalent to `(x<=y ? 1 : 0) <= z', which is a different interpretation from that of ordinary mathematical notation. * Storage-class specifiers like `static' are not the first things in a declaration. According to the C Standard, this usage is obsolescent. * If `-Wall' or `-Wunused' is also specified, warn about unused arguments. * A comparison between signed and unsigned values could produce an incorrect result when the signed value is converted to unsigned. (But don't warn if `-Wno-sign-compare' is also specified.) * An aggregate has a partly bracketed initializer. For example, the following code would evoke such a warning, because braces are missing around the initializer for `x.h': struct s { int f, g; }; struct t { struct s h; int i; }; struct t x = { 1, 2, 3 }; * An aggregate has an initializer which does not initialize all members. For example, the following code would cause such a warning, because `x.h' would be implicitly initialized to zero: struct s { int f, g, h; }; struct s x = { 3, 4 }; `-Wtraditional' Warn about certain constructs that behave differently in traditional and ANSI C. * Macro arguments occurring within string constants in the macro body. These would substitute the argument in traditional C, but are part of the constant in ANSI C. * A function declared external in one block and then used after the end of the block. * A `switch' statement has an operand of type `long'. * A non-`static' function declaration follows a `static' one. This construct is not accepted by some traditional C compilers. `-Wundef' Warn if an undefined identifier is evaluated in an `#if' directive. `-Wshadow' Warn whenever a local variable shadows another local variable. `-Wid-clash-LEN' Warn whenever two distinct identifiers match in the first LEN characters. This may help you prepare a program that will compile with certain obsolete, brain-damaged compilers. `-Wlarger-than-LEN' Warn whenever an object of larger than LEN bytes is defined. `-Wpointer-arith' Warn about anything that depends on the "size of" a function type or of `void'. GNU C assigns these types a size of 1, for convenience in calculations with `void *' pointers and pointers to functions. `-Wbad-function-cast' Warn whenever a function call is cast to a non-matching type. For example, warn if `int malloc()' is cast to `anything *'. `-Wcast-qual' Warn whenever a pointer is cast so as to remove a type qualifier from the target type. For example, warn if a `const char *' is cast to an ordinary `char *'. `-Wcast-align' Warn whenever a pointer is cast such that the required alignment of the target is increased. For example, warn if a `char *' is cast to an `int *' on machines where integers can only be accessed at two- or four-byte boundaries. `-Wwrite-strings' Give string constants the type `const char[LENGTH]' so that copying the address of one into a non-`const' `char *' pointer will get a warning. These warnings will help you find at compile time code that can try to write into a string constant, but only if you have been very careful about using `const' in declarations and prototypes. Otherwise, it will just be a nuisance; this is why we did not make `-Wall' request these warnings. `-Wconversion' Warn if a prototype causes a type conversion that is different from what would happen to the same argument in the absence of a prototype. This includes conversions of fixed point to floating and vice versa, and conversions changing the width or signedness of a fixed point argument except when the same as the default promotion. Also, warn if a negative integer constant expression is implicitly converted to an unsigned type. For example, warn about the assignment `x = -1' if `x' is unsigned. But do not warn about explicit casts like `(unsigned) -1'. `-Wsign-compare' Warn when a comparison between signed and unsigned values could produce an incorrect result when the signed value is converted to unsigned. This warning is also enabled by `-W'; to get the other warnings of `-W' without this warning, use `-W -Wno-sign-compare'. `-Waggregate-return' Warn if any functions that return structures or unions are defined or called. (In languages where you can return an array, this also elicits a warning.) `-Wstrict-prototypes' Warn if a function is declared or defined without specifying the argument types. (An old-style function definition is permitted without a warning if preceded by a declaration which specifies the argument types.) `-Wmissing-prototypes' Warn if a global function is defined without a previous prototype declaration. This warning is issued even if the definition itself provides a prototype. The aim is to detect global functions that fail to be declared in header files. `-Wmissing-declarations' Warn if a global function is defined without a previous declaration. Do so even if the definition itself provides a prototype. Use this option to detect global functions that are not declared in header files. `-Wmissing-noreturn' Warn about functions which might be candidates for attribute `noreturn'. Note these are only possible candidates, not absolute ones. Care should be taken to manually verify functions actually do not ever return before adding the `noreturn' attribute, otherwise subtle code generation bugs could be introduced. `-Wredundant-decls' Warn if anything is declared more than once in the same scope, even in cases where multiple declaration is valid and changes nothing. `-Wnested-externs' Warn if an `extern' declaration is encountered within an function. `-Winline' Warn if a function can not be inlined, and either it was declared as inline, or else the `-finline-functions' option was given. `-Wlong-long' Warn if `long long' type is used. This is default. To inhibit the warning messages, use `-Wno-long-long'. Flags `-Wlong-long' and `-Wno-long-long' are taken into account only when `-pedantic' flag is used. `-Werror' Make all warnings into errors.