@gccoptlist{-fmessage-length=@var{n} @gol
-fdiagnostics-show-location=@r{[}once@r{|}every-line@r{]} @gol
-fdiagnostics-color=@r{[}auto@r{|}never@r{|}always@r{]} @gol
+-fdiagnostics-urls=@r{[}auto@r{|}never@r{|}always@r{]} @gol
-fdiagnostics-format=@r{[}text@r{|}json@r{]} @gol
-fno-diagnostics-show-option -fno-diagnostics-show-caret @gol
-fno-diagnostics-show-labels -fno-diagnostics-show-line-numbers @gol
-Winaccessible-base @gol
-Winit-self -Winline -Wno-int-conversion -Wint-in-bool-context @gol
-Wno-int-to-pointer-cast -Winvalid-memory-model -Wno-invalid-offsetof @gol
+-Wzero-length-bounds @gol
-Winvalid-pch -Wlarger-than=@var{byte-size} @gol
-Wlogical-op -Wlogical-not-parentheses -Wlong-long @gol
-Wmain -Wmaybe-uninitialized -Wmemset-elt-size -Wmemset-transposed-args @gol
-Wno-pragmas -Wno-prio-ctor-dtor -Wredundant-decls @gol
-Wrestrict -Wno-return-local-addr @gol
-Wreturn-type -Wsequence-point -Wshadow -Wno-shadow-ivar @gol
--Wshadow=global, -Wshadow=local, -Wshadow=compatible-local @gol
+-Wshadow=global -Wshadow=local -Wshadow=compatible-local @gol
-Wshift-overflow -Wshift-overflow=@var{n} @gol
-Wshift-count-negative -Wshift-count-overflow -Wshift-negative-value @gol
-Wsign-compare -Wsign-conversion -Wfloat-conversion @gol
-Wsizeof-pointer-memaccess -Wsizeof-array-argument @gol
-Wstack-protector -Wstack-usage=@var{byte-size} -Wstrict-aliasing @gol
-Wstrict-aliasing=n -Wstrict-overflow -Wstrict-overflow=@var{n} @gol
+-Wstring-compare @gol
-Wstringop-overflow=@var{n} -Wstringop-truncation -Wsubobject-linkage @gol
-Wsuggest-attribute=@r{[}pure@r{|}const@r{|}noreturn@r{|}format@r{|}malloc@r{]} @gol
-Wsuggest-final-types @gol -Wsuggest-final-methods -Wsuggest-override @gol
-falign-jumps[=@var{n}[:@var{m}:[@var{n2}[:@var{m2}]]]] @gol
-falign-labels[=@var{n}[:@var{m}:[@var{n2}[:@var{m2}]]]] @gol
-falign-loops[=@var{n}[:@var{m}:[@var{n2}[:@var{m2}]]]] @gol
+-fallow-store-data-races @gol
-fassociative-math -fauto-profile -fauto-profile[=@var{path}] @gol
-fauto-inc-dec -fbranch-probabilities @gol
--fbranch-target-load-optimize -fbranch-target-load-optimize2 @gol
--fbtr-bb-exclusive -fcaller-saves @gol
+-fcaller-saves @gol
-fcombine-stack-adjustments -fconserve-stack @gol
-fcompare-elim -fcprop-registers -fcrossjumping @gol
-fcse-follow-jumps -fcse-skip-blocks -fcx-fortran-rules @gol
-march=@var{name} -mcpu=@var{name} -mtune=@var{name} @gol
-moverride=@var{string} -mverbose-cost-dump @gol
-mstack-protector-guard=@var{guard} -mstack-protector-guard-reg=@var{sysreg} @gol
--mstack-protector-guard-offset=@var{offset} -mtrack-speculation }
+-mstack-protector-guard-offset=@var{offset} -mtrack-speculation @gol
+-moutline-atomics }
@emph{Adapteva Epiphany Options}
@gccoptlist{-mhalf-reg-file -mprefer-short-insn-regs @gol
-mrestrict-it @gol
-mverbose-cost-dump @gol
-mpure-code @gol
--mcmse}
+-mcmse @gol
+-mfdpic}
@emph{AVR Options}
@gccoptlist{-mmcu=@var{mcu} -mabsdata -maccumulate-args @gol
-msmall-text -mlarge-text @gol
-mmemory-latency=@var{time}}
+@emph{eBPF Options}
+@gccoptlist{-mbig-endian -mlittle-endian -mkernel=@var{version}
+-mframe-limit=@var{bytes}}
+
@emph{FR30 Options}
@gccoptlist{-msmall-model -mno-lsim}
-mwarn-mcu @gol
-mcode-region= -mdata-region= @gol
-msilicon-errata= -msilicon-errata-warn= @gol
--mhwmult= -minrt}
+-mhwmult= -minrt -mtiny-printf}
@emph{NDS32 Options}
@gccoptlist{-mbig-endian -mlittle-endian @gol
Version 13, which first appeared in G++ 8.2, fixes the accidental
change in version 12.
+Version 14, which first appeared in G++ 10, corrects the mangling of
+the nullptr expression.
+
See also @option{-Wabi}.
@item -fabi-compat-version=@var{n}
@samp{new (nothrow)}.
@item -fconcepts
+@itemx -fconcepts-ts
@opindex fconcepts
-Enable support for the C++ Extensions for Concepts Technical
-Specification, ISO 19217 (2015), which allows code like
+@opindex fconcepts-ts
+Below @option{-std=c++2a}, @option{-fconcepts} enables support for the
+C++ Extensions for Concepts Technical Specification, ISO 19217 (2015).
-@smallexample
-template <class T> concept bool Addable = requires (T t) @{ t + t; @};
-template <Addable T> T add (T a, T b) @{ return a + b; @}
-@end smallexample
+With @option{-std=c++2a} and above, Concepts are part of the language
+standard, so @option{-fconcepts} defaults to on. But the standard
+specification of Concepts differs significantly from the TS, so some
+constructs that were allowed in the TS but didn't make it into the
+standard can still be enabled by @option{-fconcepts-ts}.
@item -fconstexpr-depth=@var{n}
@opindex fconstexpr-depth
arguments in the C++ frontend.
@end table
+@item -fdiagnostics-urls[=@var{WHEN}]
+@opindex fdiagnostics-urls
+@cindex urls
+Use escape sequences to embed URLs in diagnostics. For example, when
+@option{-fdiagnostics-show-option} emits text showing the command-line
+option controlling a diagnostic, embed a URL for documentation of that
+option.
+
+@var{WHEN} is @samp{never}, @samp{always}, or @samp{auto}.
+The default is @samp{auto}, which means to use URL escape sequences only
+when the standard error is a terminal.
+
@item -fno-diagnostics-show-option
@opindex fno-diagnostics-show-option
@opindex fdiagnostics-show-option
],
"message": "this \u2018if\u2019 clause does not guard...",
"option": "-Wmisleading-indentation",
+ "option_url": "https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html#index-Wmisleading-indentation",
"children": [
@{
"kind": "note",
-Wimplicit-int @r{(C and Objective-C only)} @gol
-Wimplicit-function-declaration @r{(C and Objective-C only)} @gol
-Winit-self @r{(only for C++)} @gol
+-Wzero-length-bounds @gol
-Wlogical-not-parentheses @gol
-Wmain @r{(only for C/ObjC and unless} @option{-ffreestanding}@r{)} @gol
-Wmaybe-uninitialized @gol
-Wold-style-declaration @r{(C only)} @gol
-Woverride-init @gol
-Wsign-compare @r{(C only)} @gol
+-Wstring-compare @gol
-Wredundant-move @r{(only for C++)} @gol
-Wtype-limits @gol
-Wuninitialized @gol
@item -Wuninitialized
@opindex Wuninitialized
@opindex Wno-uninitialized
-Warn if an automatic variable is used without first being initialized
-or if a variable may be clobbered by a @code{setjmp} call. In C++,
-warn if a non-static reference or non-static @code{const} member
-appears in a class without constructors.
+Warn if an automatic variable is used without first being initialized.
+In C++, warn if a non-static reference or non-static @code{const}
+member appears in a class without constructors.
If you want to warn about code that uses the uninitialized value of the
variable in its own initializer, use the @option{-Winit-self} option.
-These warnings occur for individual uninitialized or clobbered
-elements of structure, union or array variables as well as for
-variables that are uninitialized or clobbered as a whole. They do
-not occur for variables or elements declared @code{volatile}. Because
-these warnings depend on optimization, the exact variables or elements
-for which there are warnings depends on the precise optimization
-options and version of GCC used.
+These warnings occur for individual uninitialized elements of
+structure, union or array variables as well as for variables that are
+uninitialized as a whole. They do not occur for variables or elements
+declared @code{volatile}. Because these warnings depend on
+optimization, the exact variables or elements for which there are
+warnings depend on the precise optimization options and version of GCC
+used.
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
false positives.
@end table
+@item -Wstring-compare
+@opindex Wstring-compare
+@opindex Wno-string-compare
+Warn for calls to @code{strcmp} and @code{strncmp} whose result is
+determined to be either zero or non-zero in tests for such equality
+owing to the length of one argument being greater than the size of
+the array the other argument is stored in (or the bound in the case
+of @code{strncmp}). Such calls could be mistakes. For example,
+the call to @code{strcmp} below is diagnosed because its result is
+necessarily non-zero irrespective of the contents of the array @code{a}.
+
+@smallexample
+extern char a[4];
+void f (char *d)
+@{
+ strcpy (d, "string");
+ @dots{}
+ if (0 == strcmp (a, d)) // cannot be true
+ puts ("a and d are the same");
+@}
+@end smallexample
+
+@option{-Wstring-compare} is enabled by @option{-Wextra}.
+
@item -Wstringop-overflow
@itemx -Wstringop-overflow=@var{type}
@opindex Wstringop-overflow
@opindex Wno-discarded-array-qualifiers
@opindex Wdiscarded-array-qualifiers
Do not warn if type qualifiers on arrays which are pointer targets
-are being discarded. Typically, the compiler warns if a
+are being discarded. Typically, the compiler warns if a
@code{const int (*)[]} variable is passed to a function that
takes a @code{int (*)[]} parameter. This option can be used to
suppress such a warning.
conversions the warnings @option{-Wno-int-to-pointer-cast} and
@option{-Wno-pointer-to-int-cast} may be used.
+@item -Wzero-length-bounds
+@opindex Wzero-length-bounds
+@opindex Wzero-length-bounds
+Warn about accesses to elements of zero-length array members that might
+overlap other members of the same object. Declaring interior zero-length
+arrays is discouraged because accesses to them are undefined. See
+@xref{Zero Length}.
+
+For example, the first two stores in function @code{bad} are diagnosed
+because the array elements overlap the subsequent members @code{b} and
+@code{c}. The third store is diagnosed by @option{-Warray-bounds}
+because it is beyond the bounds of the enclosing object.
+
+@smallexample
+struct X @{ int a[0]; int b, c; @};
+struct X x;
+
+void bad (void)
+@{
+ x.a[0] = 0; // -Wzero-length-bounds
+ x.a[1] = 1; // -Wzero-length-bounds
+ x.a[2] = 2; // -Warray-bounds
+@}
+@end smallexample
+
+Option @option{-Wzero-length-bounds} is enabled by @option{-Warray-bounds}.
+
@item -Wno-div-by-zero
@opindex Wno-div-by-zero
@opindex Wdiv-by-zero
@opindex Wno-shadow
Warn whenever a local variable or type declaration shadows another
variable, parameter, type, class member (in C++), or instance variable
-(in Objective-C) or whenever a built-in function is shadowed. Note
+(in Objective-C) or whenever a built-in function is shadowed. Note
that in C++, the compiler warns if a local variable shadows an
explicit typedef, but not if it shadows a struct/class/enum.
+If this warning is enabled, it includes also all instances of
+local shadowing. This means that @option{-Wno-shadow=local}
+and @option{-Wno-shadow=compatible-local} are ignored when
+@option{-Wshadow} is used.
Same as @option{-Wshadow=global}.
@item -Wno-shadow-ivar @r{(Objective-C only)}
Objective-C method.
@item -Wshadow=global
-@opindex Wshadow=local
-The default for @option{-Wshadow}. Warns for any (global) shadowing.
+@opindex Wshadow=global
+Warn for any shadowing.
+Same as @option{-Wshadow}.
@item -Wshadow=local
@opindex Wshadow=local
Warn when a local variable shadows another local variable or parameter.
-This warning is enabled by @option{-Wshadow=global}.
@item -Wshadow=compatible-local
@opindex Wshadow=compatible-local
Warn when a local variable shadows another local variable or parameter
-whose type is compatible with that of the shadowing variable. In C++,
+whose type is compatible with that of the shadowing variable. In C++,
type compatibility here means the type of the shadowing variable can be
-converted to that of the shadowed variable. The creation of this flag
+converted to that of the shadowed variable. The creation of this flag
(in addition to @option{-Wshadow=local}) is based on the idea that when
a local variable shadows another one of incompatible type, it is most
likely intentional, not a bug or typo, as shown in the following example:
@end smallexample
Since the two variable @code{i} in the example above have incompatible types,
-enabling only @option{-Wshadow=compatible-local} will not emit a warning.
+enabling only @option{-Wshadow=compatible-local} does not emit a warning.
Because their types are incompatible, if a programmer accidentally uses one
-in place of the other, type checking will catch that and emit an error or
-warning. So not warning (about shadowing) in this case will not lead to
-undetected bugs. Use of this flag instead of @option{-Wshadow=local} can
+in place of the other, type checking is expected to catch that and emit an
+error or warning. Use of this flag instead of @option{-Wshadow=local} can
possibly reduce the number of warnings triggered by intentional shadowing.
+Note that this also means that shadowing @code{const char *i} by
+@code{char *i} does not emit a warning.
-This warning is enabled by @option{-Wshadow=local}.
+This warning is also enabled by @option{-Wshadow=local}.
@item -Wlarger-than=@var{byte-size}
@opindex Wlarger-than=
-ffinite-loops @gol
-fgcse -fgcse-lm @gol
-fhoist-adjacent-loads @gol
+-finline-functions @gol
-finline-small-functions @gol
-findirect-inlining @gol
-fipa-bit-cp -fipa-cp -fipa-icf @gol
@c Please keep the following list alphabetized!
@gccoptlist{-fgcse-after-reload @gol
--finline-functions @gol
-fipa-cp-clone
-floop-interchange @gol
-floop-unroll-and-jam @gol
Disregard strict standards compliance. @option{-Ofast} enables all
@option{-O3} optimizations. It also enables optimizations that are not
valid for all standard-compliant programs.
-It turns on @option{-ffast-math} and the Fortran-specific
-@option{-fstack-arrays}, unless @option{-fmax-stack-var-size} is
-specified, and @option{-fno-protect-parens}.
+It turns on @option{-ffast-math}, @option{-fallow-store-data-races}
+and the Fortran-specific @option{-fstack-arrays}, unless
+@option{-fmax-stack-var-size} is specified, and @option{-fno-protect-parens}.
@item -Og
@opindex Og
declared @code{static}, then the function is normally not output as
assembler code in its own right.
-Enabled at levels @option{-O3}, @option{-Os}. Also enabled
+Enabled at levels @option{-O2}, @option{-O3}, @option{-Os}. Also enabled
by @option{-fprofile-use} and @option{-fauto-profile}.
@item -finline-functions-called-once
Enabled at levels @option{-O2}, @option{-O3}.
+@item -fallow-store-data-races
+@opindex fallow-store-data-races
+Allow the compiler to introduce new data races on stores.
+
+Enabled at level @option{-Ofast}.
+
@item -funit-at-a-time
@opindex funit-at-a-time
This option is left for compatibility reasons. @option{-funit-at-a-time}
precedence; and for example @option{-ffp-contract=off} takes precedence
over @option{-ffp-contract=fast}. You can override them at link time.
+To enable debug info generation you need to supply @option{-g} at
+compile-time. If any of the input files at link time were built
+with debug info generation enabled the link will enable debug info
+generation as well. Any elaborate debug info settings
+like the dwarf level @option{-gdwarf-5} need to be explicitly repeated
+at the linker command line and mixing different settings in different
+translation units is discouraged.
+
If LTO encounters objects with C linkage declared with incompatible
types in separate translation units to be linked together (undefined
behavior according to ISO C99 6.2.7), a non-fatal diagnostic may be
double} variants, to generate code that raises the ``inexact''
floating-point exception for noninteger arguments. ISO C99 and C11
allow these functions to raise the ``inexact'' exception, but ISO/IEC
-TS 18661-1:2014, the C bindings to IEEE 754-2008, does not allow these
-functions to do so.
+TS 18661-1:2014, the C bindings to IEEE 754-2008, as integrated into
+ISO C2X, does not allow these functions to do so.
The default is @option{-ffp-int-builtin-inexact}, allowing the
-exception to be raised. This option does nothing unless
-@option{-ftrapping-math} is in effect.
+exception to be raised, unless C2X or a later C standard is selected.
+This option does nothing unless @option{-ftrapping-math} is in effect.
Even if @option{-fno-fp-int-builtin-inexact} is used, if the functions
generate a call to a library function then the ``inexact'' exception
link time. An example of such an optimization is relaxing calls to short call
instructions.
-@item -fbranch-target-load-optimize
-@opindex fbranch-target-load-optimize
-Perform branch target register load optimization before prologue / epilogue
-threading.
-The use of target registers can typically be exposed only during reload,
-thus hoisting loads out of loops and doing inter-block scheduling needs
-a separate optimization pass.
-
-@item -fbranch-target-load-optimize2
-@opindex fbranch-target-load-optimize2
-Perform branch target register load optimization after prologue / epilogue
-threading.
-
-@item -fbtr-bb-exclusive
-@opindex fbtr-bb-exclusive
-When performing branch target register load optimization, don't reuse
-branch target registers within any basic block.
-
@item -fstdarg-opt
@opindex fstdarg-opt
Optimize the prologue of variadic argument functions with respect to usage of
compilation time.
@item max-inline-insns-single
-Several parameters control the tree inliner used in GCC@.
-This number sets the maximum number of instructions (counted in GCC's
-internal representation) in a single function that the tree inliner
-considers for inlining. This only affects functions declared
-inline and methods implemented in a class declaration (C++).
+@item max-inline-insns-single-O2
+Several parameters control the tree inliner used in GCC@. This number sets the
+maximum number of instructions (counted in GCC's internal representation) in a
+single function that the tree inliner considers for inlining. This only
+affects functions declared inline and methods implemented in a class
+declaration (C++).
+
+For functions compiled with optimization levels
+@option{-O3} and @option{-Ofast} parameter @option{max-inline-insns-single} is
+applied. In other cases @option{max-inline-insns-single-O2} is applied.
+
@item max-inline-insns-auto
+@item max-inline-insns-auto-O2
When you use @option{-finline-functions} (included in @option{-O3}),
a lot of functions that would otherwise not be considered for inlining
by the compiler are investigated. To those functions, a different
(more restrictive) limit compared to functions declared inline can
be applied.
+For functions compiled with optimization levels
+@option{-O3} and @option{-Ofast} parameter @option{max-inline-insns-auto} is
+applied. In other cases @option{max-inline-insns-auto-O2} is applied.
+
@item max-inline-insns-small
This is bound applied to calls which are considered relevant with
@option{-finline-small-functions}.
Extra time accounted by inliner for function overhead such as time needed to
execute function prologue and epilogue
+@item inline-heuristics-hint-percent
+@item inline-heuristics-hint-percent-O2
+The scale (in percents) applied to @option{inline-insns-single},
+@option{inline-insns-single-O2}, @option{inline-insns-auto},
+@option{inline-insns-auto-O2} when inline heuristics hints that inlining is
+very profitable (will enable later optimizations).
+
+For functions compiled with optimization levels
+@option{-O3} and @option{-Ofast} parameter
+@option{inline-heuristics-hint-percent} is applied. In other cases
+@option{inline-heuristics-hint-percent-O2} is applied.
+
@item uninlined-thunk-insns
@item uninlined-thunk-time
Same as @option{--param uninlined-function-insns} and
@option{--param uninlined-function-time} but applied to function thunks
@item inline-min-speedup
+@item inline-min-speedup-O2
When estimated performance improvement of caller + callee runtime exceeds this
threshold (in percent), the function can be inlined regardless of the limit on
@option{--param max-inline-insns-single} and @option{--param
max-inline-insns-auto}.
+For functions compiled with optimization levels
+@option{-O3} and @option{-Ofast} parameter @option{inline-min-speedup} is
+applied. In other cases @option{inline-min-speedup-O2} is applied.
+
@item large-function-insns
The limit specifying really large functions. For functions larger than this
limit after inlining, inlining is constrained by
expressions whose probability exceeds the given threshold (in percents).
@item early-inlining-insns
+@item early-inlining-insns-O2
Specify growth that the early inliner can make. In effect it increases
the amount of inlining for code having a large abstraction penalty.
+For functions compiled with optimization levels
+@option{-O3} and @option{-Ofast} parameter @option{early-inlining-insns} is
+applied. In other cases @option{early-inlining-insns-O2} is applied.
+
@item max-early-inliner-iterations
Limit of iterations of the early inliner. This basically bounds
the number of nested indirect calls the early inliner can resolve.
@option{ipa-sra-ptr-growth-factor} times the size of the original
pointer parameter.
+@item ipa-sra-max-replacements
+Maximum pieces of an aggregate that IPA-SRA tracks. As a
+consequence, it is also the maximum number of replacements of a formal
+parameter.
+
@item sra-max-scalarization-size-Ospeed
@itemx sra-max-scalarization-size-Osize
The two Scalar Reduction of Aggregates passes (SRA and IPA-SRA) aim to
consider all memory clobbered after examining
@option{ipa-max-aa-steps} statements modifying memory.
+@item ipa-max-switch-predicate-bounds
+Maximal number of boundary endpoints of case ranges of switch statement.
+For switch exceeding this limit, IPA-CP will not construct cloning cost
+predicate, which is used to estimate cloning benefit, for default case
+of the switch statement.
+
+@item ipa-max-param-expr-ops
+IPA-CP will analyze conditional statement that references some function
+parameter to estimate benefit for cloning upon certain constant value.
+But if number of operations in a parameter expression exceeds
+@option{ipa-max-param-expr-ops}, the expression is treated as complicated
+one, and is not handled by IPA analysis.
+
@item lto-partitions
Specify desired number of partitions produced during WHOPR compilation.
The number of partitions should exceed the number of CPUs used for compilation.
if either vectorization (@option{-ftree-vectorize}) or if-conversion
(@option{-ftree-loop-if-convert}) is disabled.
-@item allow-store-data-races
-Allow optimizers to introduce new data races on stores.
-Set to 1 to allow, otherwise to 0.
-
@item case-values-threshold
The smallest number of different values for which it is best to use a
jump-table instead of a tree of conditional branches. If the value is
* C-SKY Options::
* Darwin Options::
* DEC Alpha Options::
+* eBPF Options::
* FR30 Options::
* FT32 Options::
* FRV Options::
@code{__builtin_speculation_safe_copy} to permit a more efficient code
sequence to be generated.
+@item -moutline-atomics
+@itemx -mno-outline-atomics
+Enable or disable calls to out-of-line helpers to implement atomic operations.
+These helpers will, at runtime, determine if the LSE instructions from
+ARMv8.1-A can be used; if not, they will use the load/store-exclusive
+instructions that are present in the base ARMv8.0 ISA.
+
+This option is only applicable when compiling for the base ARMv8.0
+instruction set. If using a later revision, e.g. @option{-march=armv8.1-a}
+or @option{-march=armv8-a+lse}, the ARMv8.1-Atomics instructions will be
+used directly. The same applies when using @option{-mcpu=} when the
+selected cpu supports the @samp{lse} feature.
+
@item -march=@var{name}
@opindex march
Specify the name of the target architecture and, optionally, one or
Generate secure code as per the "ARMv8-M Security Extensions: Requirements on
Development Tools Engineering Specification", which can be found on
@url{http://infocenter.arm.com/help/topic/com.arm.doc.ecm0359818/ECM0359818_armv8m_security_extensions_reqs_on_dev_tools_1_0.pdf}.
+
+@item -mfdpic
+@itemx -mno-fdpic
+@opindex mfdpic
+@opindex mno-fdpic
+Select the FDPIC ABI, which uses 64-bit function descriptors to
+represent pointers to functions. When the compiler is configured for
+@code{arm-*-uclinuxfdpiceabi} targets, this option is on by default
+and implies @option{-fPIE} if none of the PIC/PIE-related options is
+provided. On other targets, it only enables the FDPIC-specific code
+generation features, and the user should explicitly provide the
+PIC/PIE-related options as needed.
+
+Note that static linking is not supported because it would still
+involve the dynamic linker when the program self-relocates. If such
+behavior is acceptable, use -static and -Wl,-dynamic-linker options.
+
+The opposite @option{-mno-fdpic} option is useful (and required) to
+build the Linux kernel using the same (@code{arm-*-uclinuxfdpiceabi})
+toolchain as the one used to build the userland programs.
+
@end table
@node AVR Options
@end table
@end table
+@node eBPF Options
+@subsection eBPF Options
+@cindex eBPF Options
+
+@table @gcctabopt
+@item -mframe-limit=@var{bytes}
+This specifies the hard limit for frame sizes, in bytes. Currently,
+the value that can be specified should be less than or equal to
+@samp{32767}. Defaults to whatever limit is imposed by the version of
+the Linux kernel targeted.
+
+@item -mkernel=@var{version}
+@opindex mkernel
+This specifies the minimum version of the kernel that will run the
+compiled program. GCC uses this version to determine which
+instructions to use, what kernel helpers to allow, etc. Currently,
+@var{version} can be one of @samp{4.0}, @samp{4.1}, @samp{4.2},
+@samp{4.3}, @samp{4.4}, @samp{4.5}, @samp{4.6}, @samp{4.7},
+@samp{4.8}, @samp{4.9}, @samp{4.10}, @samp{4.11}, @samp{4.12},
+@samp{4.13}, @samp{4.14}, @samp{4.15}, @samp{4.16}, @samp{4.17},
+@samp{4.18}, @samp{4.19}, @samp{4.20}, @samp{5.0}, @samp{5.1},
+@samp{5.2}, @samp{latest} and @samp{native}.
+
+@item -mbig-endian
+@opindex mbig-endian
+Generate code for a big-endian target.
+
+@item -mlittle-endian
+@opindex mlittle-endian
+Generate code for a little-endian target. This is the default.
+@end table
+
@node FR30 Options
@subsection FR30 Options
@cindex FR30 Options
into GCC. However, an external @samp{devices.csv} file can be used to
extend device support beyond those that have been hard-coded.
-GCC searches for the @samp{devices.csv} file on the paths specified
-with the @code{-I} and @code{-L} options.
+GCC searches for the @samp{devices.csv} file using the following methods in the
+given precedence order, where the first method takes precendence over the
+second which takes precedence over the third.
+
+@table @asis
+@item Include path specified with @code{-I} and @code{-L}
+@samp{devices.csv} will be searched for in each of the directories specified by
+include paths and linker library search paths.
+@item Path specified by the environment variable @samp{MSP430_GCC_INCLUDE_DIR}
+Define the value of the global environment variable
+@samp{MSP430_GCC_INCLUDE_DIR}
+to the full path to the directory containing devices.csv, and GCC will search
+this directory for devices.csv. If devices.csv is found, this directory will
+also be registered as an include path, and linker library path. Header files
+and linker scripts in this directory can therefore be used without manually
+specifying @code{-I} and @code{-L} on the command line.
+@item The @samp{msp430-elf/include/devices} directory
+Finally, GCC will examine @samp{msp430-elf/include/devices} from the
+toolchain root directory. This directory does not exist in a default
+installation, but if the user has created it and copied @samp{devices.csv}
+there, then the MCU data will be read. As above, this directory will
+also be registered as an include path, and linker library path.
+
+@end table
+If none of the above search methods find @samp{devices.csv}, then the
+hard-coded MCU data is used.
+
@item -mwarn-mcu
@itemx -mno-warn-mcu
devices. The compiler includes special symbols in some objects
that tell the linker and runtime which code fragments are required.
+@item -mtiny-printf
+@opindex mtiny-printf
+Enable reduced code size @code{printf} and @code{puts} library functions.
+The @samp{tiny} implementations of these functions are not reentrant, so
+must be used with caution in multi-threaded applications.
+
+Support for streams has been removed and the string to be printed will
+always be sent to stdout via the @code{write} syscall. The string is not
+buffered before it is sent to write.
+
+This option requires Newlib Nano IO, so GCC must be configured with
+@samp{--enable-newlib-nano-formatted-io}.
+
@item -mcode-region=
@itemx -mdata-region=
@opindex mcode-region
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