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apache Macro used as an actual parameter leads to compile error if the macro is not defined

Function apr_signal_block takes an int as a parameter. If SIGPIPE is not defined, then the compilation breaks as SIGPIPE is not defined as a macro anywhere in the code.

Bug fixed by commit 1f46088b38d

Type	UndeclaredIdentifier
Config	"!SIGPIPE" (1st degree)
Fix-in	mapping
Location	support/

#include <stdio.h>

#ifdef SIGPIPE
#define SIGPIPE 1
#endif

void apr_signal_block(int signal)
{
  printf("%d\n", signal);
}

int main(void)
{
  apr_signal_block(SIGPIPE); // ERROR: SIGPIPE undeclared
  return 0;
}

diff --git a/apache/simple/1f46088.c b/apache/simple/1f46088.c
--- a/apache/simple/1f46088.c
+++ b/apache/simple/1f46088.c
@@ -11,6 +11,8 @@ void apr_signal_block(int signal)
 
 int main(void)
 {
+#ifdef SIGPIPE
   apr_signal_block(SIGPIPE); // ERROR: SIGPIPE undeclared
+#endif
   return 0;
 }

. ERROR firehose.c:681:apr_signal_block(SIGPIPE);