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copied!<p>This is the expected behavior.</p> <blockquote> <p>Conditional Statements</p> <p>All instances of conditional syntax are parsed immediately, in their entirety; this includes the ifdef, ifeq, ifndef, and ifneq forms. <strong>Of course this means that automatic variables cannot be used in conditional statements, as automatic variables are not set until the command script for that rule is invoked</strong>. If you need to use automatic variables in a conditional you must use shell conditional syntax, in your command script proper, for these tests, not make conditionals.</p> </blockquote> <p><strong><code>$(*D)</code> is an automatic variable.</strong></p> <p>Instead, consider doing:</p> <pre><code>.c.o .cpp.o .cc.o: $(CC) $(DEBUG_FLAGS) $(if $(subst mySpecialDirectory,,$(*D)),$(NOTTHATSPECIALFLAGS),$(MYSPECIALFLAGS)) -c $< -o $@ </code></pre> <p>The idea is to abuse <code>$(subst)</code> into some equality testing by replacing <code>mySpecialDirectory</code> with the empty string. Then, if <code>$(*D)</code> expansion equals to <code>mySpecialDirectory</code>, it is fully replaced by the empty string and the else-part of <code>$(if)</code> gets evaluated as per:</p> <blockquote> <p><code>$(if condition,then-part[,else-part])</code></p> <p>The if function provides support for conditional expansion in a functional context (as opposed to the GNU make makefile conditionals such as ifeq (see Syntax of Conditionals).</p> <p>The first argument, condition, first has all preceding and trailing whitespace stripped, then is expanded. If it expands to any non-empty string, then the condition is considered to be true. If it expands to an empty string, the condition is considered to be false.</p> </blockquote> <p>Notice the flip in this hack between the <code>then-part</code> and the <code>else-part</code>.</p> <p>Hope this helps!</p>

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