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 <a name="Breakpoint_002drelated-Warnings"></a>
 <div class="header">
 <p>
 Previous: <a href="Error-in-Breakpoints.html#Error-in-Breakpoints" accesskey="p" rel="prev">Error in Breakpoints</a>, Up: <a href="Breakpoints.html#Breakpoints" accesskey="u" rel="up">Breakpoints</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p>
 </div>
 <hr>
 <a name="g_t_0060_0060Breakpoint-address-adjusted_002e_002e_002e_0027_0027"></a>
 <h4 class="subsection">5.1.12 &ldquo;Breakpoint address adjusted...&rdquo;</h4>
 <a name="index-breakpoint-address-adjusted"></a>

 <p>Some processor architectures place constraints on the addresses at
 which breakpoints may be placed.  For architectures thus constrained,
 <small>GDB</small> will attempt to adjust the breakpoint&rsquo;s address to comply
 with the constraints dictated by the architecture.
 </p>
 <p>One example of such an architecture is the Fujitsu FR-V.  The FR-V is
 a VLIW architecture in which a number of RISC-like instructions may be
 bundled together for parallel execution.  The FR-V architecture
 constrains the location of a breakpoint instruction within such a
 bundle to the instruction with the lowest address.  <small>GDB</small>
 honors this constraint by adjusting a breakpoint&rsquo;s address to the
 first in the bundle.
 </p>
 <p>It is not uncommon for optimized code to have bundles which contain
 instructions from different source statements, thus it may happen that
 a breakpoint&rsquo;s address will be adjusted from one source statement to
 another.  Since this adjustment may significantly alter <small>GDB</small>&rsquo;s
 breakpoint related behavior from what the user expects, a warning is
 printed when the breakpoint is first set and also when the breakpoint
 is hit.
 </p>
 <p>A warning like the one below is printed when setting a breakpoint
 that&rsquo;s been subject to address adjustment:
 </p>
 <div class="smallexample">
 <pre class="smallexample">warning: Breakpoint address adjusted from 0x00010414 to 0x00010410.
 </pre></div>

 <p>Such warnings are printed both for user settable and <small>GDB</small>&rsquo;s
 internal breakpoints.  If you see one of these warnings, you should
 verify that a breakpoint set at the adjusted address will have the
 desired affect.  If not, the breakpoint in question may be removed and
 other breakpoints may be set which will have the desired behavior.
 E.g., it may be sufficient to place the breakpoint at a later
 instruction.  A conditional breakpoint may also be useful in some
 cases to prevent the breakpoint from triggering too often.
 </p>
 <p><small>GDB</small> will also issue a warning when stopping at one of these
 adjusted breakpoints:
 </p>
 <div class="smallexample">
 <pre class="smallexample">warning: Breakpoint 1 address previously adjusted from 0x00010414
 to 0x00010410.
 </pre></div>

 <p>When this warning is encountered, it may be too late to take remedial
 action except in cases where the breakpoint is hit earlier or more
 frequently than expected.
 </p>
 <hr>
 <div class="header">
 <p>
 Previous: <a href="Error-in-Breakpoints.html#Error-in-Breakpoints" accesskey="p" rel="prev">Error in Breakpoints</a>, Up: <a href="Breakpoints.html#Breakpoints" accesskey="u" rel="up">Breakpoints</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p>
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	Invariant Sections being "Free Software" and "Free Software Needs
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	<a name="Breakpoint_002drelated-Warnings"></a>
	<div class="header">
	<p>
	Previous: <a href="Error-in-Breakpoints.html#Error-in-Breakpoints" accesskey="p" rel="prev">Error in Breakpoints</a>, Up: <a href="Breakpoints.html#Breakpoints" accesskey="u" rel="up">Breakpoints</a>   [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p>
	</div>
	<hr>
	<a name="g_t_0060_0060Breakpoint-address-adjusted_002e_002e_002e_0027_0027"></a>
	<h4 class="subsection">5.1.12 “Breakpoint address adjusted...”</h4>
	<a name="index-breakpoint-address-adjusted"></a>

	<p>Some processor architectures place constraints on the addresses at
	which breakpoints may be placed. For architectures thus constrained,
	<small>GDB</small> will attempt to adjust the breakpoint’s address to comply
	with the constraints dictated by the architecture.
	</p>
	<p>One example of such an architecture is the Fujitsu FR-V. The FR-V is
	a VLIW architecture in which a number of RISC-like instructions may be
	bundled together for parallel execution. The FR-V architecture
	constrains the location of a breakpoint instruction within such a
	bundle to the instruction with the lowest address. <small>GDB</small>
	honors this constraint by adjusting a breakpoint’s address to the
	first in the bundle.
	</p>
	<p>It is not uncommon for optimized code to have bundles which contain
	instructions from different source statements, thus it may happen that
	a breakpoint’s address will be adjusted from one source statement to
	another. Since this adjustment may significantly alter <small>GDB</small>’s
	breakpoint related behavior from what the user expects, a warning is
	printed when the breakpoint is first set and also when the breakpoint
	is hit.
	</p>
	<p>A warning like the one below is printed when setting a breakpoint
	that’s been subject to address adjustment:
	</p>
	<div class="smallexample">
	<pre class="smallexample">warning: Breakpoint address adjusted from 0x00010414 to 0x00010410.
	</pre></div>

	<p>Such warnings are printed both for user settable and <small>GDB</small>’s
	internal breakpoints. If you see one of these warnings, you should
	verify that a breakpoint set at the adjusted address will have the
	desired affect. If not, the breakpoint in question may be removed and
	other breakpoints may be set which will have the desired behavior.
	E.g., it may be sufficient to place the breakpoint at a later
	instruction. A conditional breakpoint may also be useful in some
	cases to prevent the breakpoint from triggering too often.
	</p>
	<p><small>GDB</small> will also issue a warning when stopping at one of these
	adjusted breakpoints:
	</p>
	<div class="smallexample">
	<pre class="smallexample">warning: Breakpoint 1 address previously adjusted from 0x00010414
	to 0x00010410.
	</pre></div>

	<p>When this warning is encountered, it may be too late to take remedial
	action except in cases where the breakpoint is hit earlier or more
	frequently than expected.
	</p>
	<hr>
	<div class="header">
	<p>
	Previous: <a href="Error-in-Breakpoints.html#Error-in-Breakpoints" accesskey="p" rel="prev">Error in Breakpoints</a>, Up: <a href="Breakpoints.html#Breakpoints" accesskey="u" rel="up">Breakpoints</a>   [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p>
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