On 13/07/17 11:26, Michael Collison wrote: > Updated per Richard's comments and suggestions. > > Okay for trunk?
OK. Please can you write up an entry for the release notes (wwwdocs). R. > > 2017-07-10 Michael Collison <michael.colli...@arm.com> > > * config/arm/arm.c (arm_option_override): Deprecate > use of -mstructure-size-boundary. > * config/arm/arm.opt: Deprecate -mstructure-size-boundary. > * doc/invoke.texi: Deprecate -mstructure-size-boundary. > > -----Original Message----- > From: Richard Earnshaw (lists) [mailto:richard.earns...@arm.com] > Sent: Thursday, July 6, 2017 3:17 AM > To: Michael Collison <michael.colli...@arm.com>; GCC Patches > <gcc-patches@gcc.gnu.org> > Cc: nd <n...@arm.com> > Subject: Re: [Arm] Obsoleting Command line option -mstructure-size-boundary > in eabi configurations > > On 06/07/17 06:46, Michael Collison wrote: >> NetBSD/Arm requires that DEFAULT_STRUCTURE_SIZE_BOUNDARY (see >> config/arm/netbsd-elf.h for details). This patch disallows >> -mstructure-size-boundary on netbsd if the value is not equal to the >> DEFAULT_STRUCTURE_SIZE_BOUNDARY. >> >> Okay for trunk? >> >> 2017-07-05 Michael Collison <michael.colli...@arm.com> >> >> * config/arm/arm.c (arm_option_override): Disallow >> -mstructure-size-boundary on netbsd if value is not >> DEFAULT_STRUCTURE_SIZE_BOUNDARY. >> >> > > Frankly, I'd rather we moved towards obsoleting this option entirely. > The origins are from the days of the APCS (note, not AAPCS) when the default > was 32 when most of the world expected 8. > > Now that the AAPCS is widely adopted, APCS is obsolete (NetBSD uses > ATPCS) and NetBSD (the only port not based on AAPCS these days) defaults to 8 > I can't see why anybody now would be interested in using a different value. > > So let's just mark this option as deprecated (emit a warning if > > global_options_set.x_arm_structure_size_boundary > > is ever set by the user, regardless of value). Then in GCC 9 we can perhaps > remove this code entirely. > > Documentation and release notes will need corresponding updates as well. > > R. > >> pr1556.patch >> >> >> diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c index >> bc1e607..911c272 100644 >> --- a/gcc/config/arm/arm.c >> +++ b/gcc/config/arm/arm.c >> @@ -3471,7 +3471,18 @@ arm_option_override (void) >> } >> else >> { >> - if (arm_structure_size_boundary != 8 >> + /* Do not allow structure size boundary to be overridden for >> + netbsd. */ >> + >> + if ((arm_abi == ARM_ABI_ATPCS) >> + && (arm_structure_size_boundary != DEFAULT_STRUCTURE_SIZE_BOUNDARY)) >> + { >> + warning (0, >> + "option %<-mstructure-size-boundary%> is deprecated for >> netbsd; " >> + "defaulting to %d", >> + DEFAULT_STRUCTURE_SIZE_BOUNDARY); >> + arm_structure_size_boundary = DEFAULT_STRUCTURE_SIZE_BOUNDARY; >> + } >> + else if (arm_structure_size_boundary != 8 >> && arm_structure_size_boundary != 32 >> && !(ARM_DOUBLEWORD_ALIGN && arm_structure_size_boundary == 64)) >> { >> > > > pr1556v2.patch > > > diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c > index c6101ef..b5dbfeb 100644 > --- a/gcc/config/arm/arm.c > +++ b/gcc/config/arm/arm.c > @@ -3489,6 +3489,8 @@ arm_option_override (void) > } > else > { > + warning (0, "option %<-mstructure-size-boundary%> is deprecated"); > + > if (arm_structure_size_boundary != 8 > && arm_structure_size_boundary != 32 > && !(ARM_DOUBLEWORD_ALIGN && arm_structure_size_boundary == 64)) > diff --git a/gcc/config/arm/arm.opt b/gcc/config/arm/arm.opt > index b6c707b..6060516 100644 > --- a/gcc/config/arm/arm.opt > +++ b/gcc/config/arm/arm.opt > @@ -192,7 +192,7 @@ Target RejectNegative Alias(mfloat-abi=, soft) > Undocumented > > mstructure-size-boundary= > Target RejectNegative Joined UInteger Var(arm_structure_size_boundary) > Init(DEFAULT_STRUCTURE_SIZE_BOUNDARY) > -Specify the minimum bit alignment of structures. > +Specify the minimum bit alignment of structures. (Deprecated). > > mthumb > Target Report RejectNegative Negative(marm) Mask(THUMB) Save > diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi > index 3e5cee8..cfe5985 100644 > --- a/gcc/doc/invoke.texi > +++ b/gcc/doc/invoke.texi > @@ -15685,6 +15685,8 @@ incompatible. Code compiled with one value cannot > necessarily expect to > work with code or libraries compiled with another value, if they exchange > information using structures or unions. > > +This option is deprecated. > + > @item -mabort-on-noreturn > @opindex mabort-on-noreturn > Generate a call to the function @code{abort} at the end of a >
