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Diffstat (limited to 'gcc/doc/gty.texi')
| -rw-r--r-- | gcc/doc/gty.texi | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/gcc/doc/gty.texi b/gcc/doc/gty.texi index d43feca..c375e24 100644 --- a/gcc/doc/gty.texi +++ b/gcc/doc/gty.texi @@ -291,6 +291,19 @@ this field is always @code{NULL}. This is used to avoid requiring backends to define certain optional structures. It doesn't work with language frontends. +@findex nested_ptr +@item nested_ptr (@var{type}, "@var{to expression}", "@var{from expression}") + +The type machinery expects all pointers to point to the start of an +object. Sometimes for abstraction purposes it's convenient to have +a pointer which points inside an object. So long as it's possible to +convert the original object to and from the pointer, such pointers +can still be used. @var{type} is the type of the original object, +the @var{to expression} returns the pointer given the original object, +and the @var{from expression} returns the original object given +the pointer. The pointer will be available using the @code{%h} +escape. + @findex chain_next @findex chain_prev @item chain_next ("@var{expression}") |