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(e.g., with <samp>-g3</samp> 73<samp>-gstabs</samp> when using GCC). 74</p> 75<p>A <code>#define <var>macro-name</var> <var>macro-body</var></code> is represented with 76an <code>N_MAC_DEFINE</code> stab with a string field of 77<code><var>macro-name</var> <var>macro-body</var></code>. 78<a name="index-N_005fMAC_005fDEFINE"></a> 79</p> 80<p>An <code>#undef <var>macro-name</var></code> is represented with an 81<code>N_MAC_UNDEF</code> stabs with a string field of simply 82<code><var>macro-name</var></code>. 83<a name="index-N_005fMAC_005fUNDEF"></a> 84</p> 85<p>For both <code>N_MAC_DEFINE</code> and <code>N_MAC_UNDEF</code>, the desc field is 86the line number within the file where the corresponding <code>#define</code> 87or <code>#undef</code> occurred. 88</p> 89<p>For example, the following C code: 90</p> 91<div class="example"> 92<pre class="example"> #define NONE 42 93 #define TWO(a, b) (a + (a) + 2 * b) 94 #define ONE(c) (c + 19) 95 96 main(int argc, char *argv[]) 97 { 98 func(NONE, TWO(10, 11)); 99 func(NONE, ONE(23)); 100 101 #undef ONE 102 #define ONE(c) (c + 23) 103 104 func(NONE, ONE(-23)); 105 106 return (0); 107 } 108 109 int global; 110 111 func(int arg1, int arg2) 112 { 113 global = arg1 + arg2; 114 } 115</pre></div> 116 117<p>produces the following stabs (as well as many others): 118</p> 119<div class="example"> 120<pre class="example"> .stabs "NONE 42",54,0,1,0 121 .stabs "TWO(a,b) (a + (a) + 2 * b)",54,0,2,0 122 .stabs "ONE(c) (c + 19)",54,0,3,0 123 .stabs "ONE",58,0,10,0 124 .stabs "ONE(c) (c + 23)",54,0,11,0 125</pre></div> 126 127<p>NOTE: In the above example, <code>54</code> is <code>N_MAC_DEFINE</code> and 128<code>58</code> is <code>N_MAC_UNDEF</code>. 129</p> 130 131 132 133</body> 134</html> 135