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diff --git a/share/doc/gccint/Stack-Smashing-Protection.html b/share/doc/gccint/Stack-Smashing-Protection.html new file mode 100644 index 0000000..198f3f7 --- /dev/null +++ b/share/doc/gccint/Stack-Smashing-Protection.html @@ -0,0 +1,139 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1988-2023 Free Software Foundation, Inc. + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with the +Invariant Sections being "Funding Free Software", the Front-Cover +Texts being (a) (see below), and with the Back-Cover Texts being (b) +(see below). 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This variable is initialized by the +runtime to some random value and is used to initialize the guard value +that is placed at the top of the local stack frame. The type of this +variable must be <code>ptr_type_node</code>. +</p> +<p>The default version of this hook creates a variable called +‘<samp>__stack_chk_guard</samp>’, which is normally defined in <samp>libgcc2.c</samp>. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fSTACK_005fPROTECT_005fFAIL"></a>Target Hook: <em>tree</em> <strong>TARGET_STACK_PROTECT_FAIL</strong> <em>(void)</em></dt> +<dd><p>This hook returns a <code>CALL_EXPR</code> that alerts the runtime that the +stack protect guard variable has been modified. This expression should +involve a call to a <code>noreturn</code> function. +</p> +<p>The default version of this hook invokes a function called +‘<samp>__stack_chk_fail</samp>’, taking no arguments. This function is +normally defined in <samp>libgcc2.c</samp>. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fSTACK_005fPROTECT_005fRUNTIME_005fENABLED_005fP"></a>Target Hook: <em>bool</em> <strong>TARGET_STACK_PROTECT_RUNTIME_ENABLED_P</strong> <em>(void)</em></dt> +<dd><p>Returns true if the target wants GCC’s default stack protect runtime support, +otherwise return false. The default implementation always returns true. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fSUPPORTS_005fSPLIT_005fSTACK"></a>Common Target Hook: <em>bool</em> <strong>TARGET_SUPPORTS_SPLIT_STACK</strong> <em>(bool <var>report</var>, struct gcc_options *<var>opts</var>)</em></dt> +<dd><p>Whether this target supports splitting the stack when the options +described in <var>opts</var> have been passed. This is called +after options have been parsed, so the target may reject splitting +the stack in some configurations. The default version of this hook +returns false. If <var>report</var> is true, this function may issue a warning +or error; if <var>report</var> is false, it must simply return a value +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fGET_005fVALID_005fOPTION_005fVALUES"></a>Common Target Hook: <em>vec<const char *></em> <strong>TARGET_GET_VALID_OPTION_VALUES</strong> <em>(int <var>option_code</var>, const char *<var>prefix</var>)</em></dt> +<dd><p>The hook is used for options that have a non-trivial list of +possible option values. OPTION_CODE is option code of opt_code +enum type. PREFIX is used for bash completion and allows an implementation +to return more specific completion based on the prefix. All string values +should be allocated from heap memory and consumers should release them. +The result will be pruned to cases with PREFIX if not NULL. +</p></dd></dl> + +<hr> +<div class="header"> +<p> +Next: <a href="Miscellaneous-Register-Hooks.html#Miscellaneous-Register-Hooks" accesskey="n" rel="next">Miscellaneous Register Hooks</a>, Previous: <a href="Shrink_002dwrapping-separate-components.html#Shrink_002dwrapping-separate-components" accesskey="p" rel="previous">Shrink-wrapping separate components</a>, Up: <a href="Stack-and-Calling.html#Stack-and-Calling" accesskey="u" rel="up">Stack and Calling</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p> +</div> + + + +</body> +</html> |