58 lines
1.9 KiB
Plaintext
58 lines
1.9 KiB
Plaintext
$OpenBSD: patch-gcc_doc_extend_texi,v 1.1 2008/10/01 04:52:19 ckuethe Exp $
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--- gcc/doc/extend.texi.orig Mon Mar 12 15:10:12 2007
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+++ gcc/doc/extend.texi Sat Sep 27 16:29:43 2008
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@@ -81,6 +81,7 @@ extensions, accepted by GCC in C89 mode and in C++.
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* Pragmas:: Pragmas accepted by GCC.
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* Unnamed Fields:: Unnamed struct/union fields within structs/unions.
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* Thread-Local:: Per-thread variables.
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+* Binary constants:: Binary constants using the @samp{0b} prefix.
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@end menu
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@node Statement Exprs
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@@ -3460,6 +3461,16 @@ placed in either the @code{.bss_below100} section or t
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@end table
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+@subsection AVR Variable Attributes
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+
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+@table @code
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+@item progmem
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+@cindex @code{progmem} variable attribute
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+The @code{progmem} attribute is used on the AVR to place data in the Program
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+Memory address space. The AVR is a Harvard Architecture processor and data
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+normally resides in the Data Memory address space.
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+@end table
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+
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@node Type Attributes
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@section Specifying Attributes of Types
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@cindex attribute of types
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@@ -10372,6 +10383,28 @@ Add after paragraph 6
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Non-@code{static} members shall not be @code{__thread}.
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@end quotation
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@end itemize
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+
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+@node Binary constants
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+@section Binary constants using the @samp{0b} prefix
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+@cindex Binary constants using the @samp{0b} prefix
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+
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+Integer constants can be written as binary constants, consisting of a
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+sequence of @samp{0} and @samp{1} digits, prefixed by @samp{0b} or
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+@samp{0B}. This is particularly useful in environments that operate a
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+lot on the bit-level (like microcontrollers).
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+
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+The following statements are identical:
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+
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+@smallexample
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+i = 42;
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+i = 0x2a;
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+i = 052;
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+i = 0b101010;
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+@end smallexample
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+
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+The type of these constants follows the same rules as for octal or
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+hexadecimal integer constants, so suffixes like @samp{L} or @samp{UL}
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+can be applied.
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@node C++ Extensions
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@chapter Extensions to the C++ Language
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