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<h3 class="section">4.2 Analysis Options</h3>

     <dl>
<dt><code>-a</code><dt><code>--no-static</code><dd>The &lsquo;<samp><span class="samp">-a</span></samp>&rsquo; option causes <code>gprof</code> to suppress the printing of
statically declared (private) functions.  (These are functions whose
names are not listed as global, and which are not visible outside the
file/function/block where they were defined.)  Time spent in these
functions, calls to/from them, etc., will all be attributed to the
function that was loaded directly before it in the executable file. 
<!-- This is compatible with Unix @code{gprof}, but a bad idea. -->
This option affects both the flat profile and the call graph.

     <br><dt><code>-c</code><dt><code>--static-call-graph</code><dd>The &lsquo;<samp><span class="samp">-c</span></samp>&rsquo; option causes the call graph of the program to be
augmented by a heuristic which examines the text space of the object
file and identifies function calls in the binary machine code. 
Since normal call graph records are only generated when functions are
entered, this option identifies children that could have been called,
but never were.  Calls to functions that were not compiled with
profiling enabled are also identified, but only if symbol table
entries are present for them. 
Calls to dynamic library routines are typically <em>not</em> found
by this option. 
Parents or children identified via this heuristic
are indicated in the call graph with call counts of &lsquo;<samp><span class="samp">0</span></samp>&rsquo;.

     <br><dt><code>-D</code><dt><code>--ignore-non-functions</code><dd>The &lsquo;<samp><span class="samp">-D</span></samp>&rsquo; option causes <code>gprof</code> to ignore symbols which
are not known to be functions.  This option will give more accurate
profile data on systems where it is supported (Solaris and HPUX for
example).

     <br><dt><code>-k </code><var>from</var><code>/</code><var>to</var><dd>The &lsquo;<samp><span class="samp">-k</span></samp>&rsquo; option allows you to delete from the call graph any arcs from
symbols matching symspec <var>from</var> to those matching symspec <var>to</var>.

     <br><dt><code>-l</code><dt><code>--line</code><dd>The &lsquo;<samp><span class="samp">-l</span></samp>&rsquo; option enables line-by-line profiling, which causes
histogram hits to be charged to individual source code lines,
instead of functions.  This feature only works with programs compiled
by older versions of the <code>gcc</code> compiler.  Newer versions of
<code>gcc</code> are designed to work with the <code>gcov</code> tool instead.

     <p>If the program was compiled with basic-block counting enabled,
this option will also identify how many times each line of
code was executed. 
While line-by-line profiling can help isolate where in a large function
a program is spending its time, it also significantly increases
the running time of <code>gprof</code>, and magnifies statistical
inaccuracies. 
See <a href="Sampling-Error.html#Sampling-Error">Statistical Sampling Error</a>.

     <br><dt><code>-m </code><var>num</var><dt><code>--min-count=</code><var>num</var><dd>This option affects execution count output only. 
Symbols that are executed less than <var>num</var> times are suppressed.

     <br><dt><code>-n</code><var>symspec</var><dt><code>--time=</code><var>symspec</var><dd>The &lsquo;<samp><span class="samp">-n</span></samp>&rsquo; option causes <code>gprof</code>, in its call graph analysis,
to only propagate times for symbols matching <var>symspec</var>.

     <br><dt><code>-N</code><var>symspec</var><dt><code>--no-time=</code><var>symspec</var><dd>The &lsquo;<samp><span class="samp">-n</span></samp>&rsquo; option causes <code>gprof</code>, in its call graph analysis,
not to propagate times for symbols matching <var>symspec</var>.

     <br><dt><code>-S</code><var>filename</var><dt><code>--external-symbol-table=</code><var>filename</var><dd>The &lsquo;<samp><span class="samp">-S</span></samp>&rsquo; option causes <code>gprof</code> to read an external symbol table
file, such as <samp><span class="file">/proc/kallsyms</span></samp>, rather than read the symbol table
from the given object file (the default is <code>a.out</code>). This is useful
for profiling kernel modules.

     <br><dt><code>-z</code><dt><code>--display-unused-functions</code><dd>If you give the &lsquo;<samp><span class="samp">-z</span></samp>&rsquo; option, <code>gprof</code> will mention all
functions in the flat profile, even those that were never called, and
that had no time spent in them.  This is useful in conjunction with the
&lsquo;<samp><span class="samp">-c</span></samp>&rsquo; option for discovering which routines were never called.

</dl>

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