| Message ID | alpine.DEB.2.22.394.2209081931360.2813963@digraph.polyomino.org.uk |
|---|---|
| State | New |
| Headers | show |
| Series | stddef.h: Add C2x unreachable macro | expand |
On Thu, Sep 8, 2022 at 9:32 PM Joseph Myers <joseph@codesourcery.com> wrote: > > C2x adds a macro unreachable to stddef.h, with the same semantics as > __builtin_unreachable. Define this macro accordingly. > > Bootstrapped with no regressions for x86_64-pc-linux-gnu. OK to commit? OK. > gcc/ > * ginclude/stddef.h [__STDC_VERSION__ > 201710L] (unreachable): > New macro. > > gcc/testsuite/ > * gcc.dg/c11-unreachable-1.c, gcc.dg/c2x-unreachable-1.c: New > tests. > > diff --git a/gcc/ginclude/stddef.h b/gcc/ginclude/stddef.h > index 315ff786694..3d29213e8f1 100644 > --- a/gcc/ginclude/stddef.h > +++ b/gcc/ginclude/stddef.h > @@ -451,6 +451,10 @@ typedef struct { > #endif > #endif /* C23. */ > > +#if defined __STDC_VERSION__ && __STDC_VERSION__ > 201710L > +#define unreachable() (__builtin_unreachable ()) > +#endif > + > #endif /* _STDDEF_H was defined this time */ > > #endif /* !_STDDEF_H && !_STDDEF_H_ && !_ANSI_STDDEF_H && !__STDDEF_H__ > diff --git a/gcc/testsuite/gcc.dg/c11-unreachable-1.c b/gcc/testsuite/gcc.dg/c11-unreachable-1.c > new file mode 100644 > index 00000000000..28e48392ed1 > --- /dev/null > +++ b/gcc/testsuite/gcc.dg/c11-unreachable-1.c > @@ -0,0 +1,9 @@ > +/* Test unreachable not defined in <stddef.h> for C11. */ > +/* { dg-do preprocess } */ > +/* { dg-options "-std=c11 -pedantic-errors" } */ > + > +#include <stddef.h> > + > +#ifdef unreachable > +#error "unreachable defined" > +#endif > diff --git a/gcc/testsuite/gcc.dg/c2x-unreachable-1.c b/gcc/testsuite/gcc.dg/c2x-unreachable-1.c > new file mode 100644 > index 00000000000..468f1f87ebb > --- /dev/null > +++ b/gcc/testsuite/gcc.dg/c2x-unreachable-1.c > @@ -0,0 +1,29 @@ > +/* Test unreachable in <stddef.h> for C2x. */ > +/* { dg-do run } */ > +/* { dg-options "-std=c2x -pedantic-errors -O2" } */ > + > +#include <stddef.h> > + > +#ifndef unreachable > +#error "unreachable not defined" > +#endif > + > +extern void *p; > +extern __typeof__ (unreachable ()) *p; > + > +volatile int x = 1; > + > +extern void not_defined (void); > + > +extern void exit (int); > + > +int > +main () > +{ > + if (x == 2) > + { > + unreachable (); > + not_defined (); > + } > + exit (0); > +} > > -- > Joseph S. Myers > joseph@codesourcery.com
diff --git a/gcc/ginclude/stddef.h b/gcc/ginclude/stddef.h index 315ff786694..3d29213e8f1 100644 --- a/gcc/ginclude/stddef.h +++ b/gcc/ginclude/stddef.h @@ -451,6 +451,10 @@ typedef struct { #endif #endif /* C23. */ +#if defined __STDC_VERSION__ && __STDC_VERSION__ > 201710L +#define unreachable() (__builtin_unreachable ()) +#endif + #endif /* _STDDEF_H was defined this time */ #endif /* !_STDDEF_H && !_STDDEF_H_ && !_ANSI_STDDEF_H && !__STDDEF_H__ diff --git a/gcc/testsuite/gcc.dg/c11-unreachable-1.c b/gcc/testsuite/gcc.dg/c11-unreachable-1.c new file mode 100644 index 00000000000..28e48392ed1 --- /dev/null +++ b/gcc/testsuite/gcc.dg/c11-unreachable-1.c @@ -0,0 +1,9 @@ +/* Test unreachable not defined in <stddef.h> for C11. */ +/* { dg-do preprocess } */ +/* { dg-options "-std=c11 -pedantic-errors" } */ + +#include <stddef.h> + +#ifdef unreachable +#error "unreachable defined" +#endif diff --git a/gcc/testsuite/gcc.dg/c2x-unreachable-1.c b/gcc/testsuite/gcc.dg/c2x-unreachable-1.c new file mode 100644 index 00000000000..468f1f87ebb --- /dev/null +++ b/gcc/testsuite/gcc.dg/c2x-unreachable-1.c @@ -0,0 +1,29 @@ +/* Test unreachable in <stddef.h> for C2x. */ +/* { dg-do run } */ +/* { dg-options "-std=c2x -pedantic-errors -O2" } */ + +#include <stddef.h> + +#ifndef unreachable +#error "unreachable not defined" +#endif + +extern void *p; +extern __typeof__ (unreachable ()) *p; + +volatile int x = 1; + +extern void not_defined (void); + +extern void exit (int); + +int +main () +{ + if (x == 2) + { + unreachable (); + not_defined (); + } + exit (0); +}