Report mem leaks to stderr if no Win debugger is present

Formerly, we sent output regarding memory leaks always to the debugger
on Windows, but this appears to be not useful especially for the PHPTs,
which usually are not run under a debugger, and so important info will
not be available there.

Author: cmb69

main/main.c

@@ -1681,7 +1681,11 @@ static ZEND_COLD void php_message_handler_for_zend(zend_long message, const void
 					snprintf(memory_leak_buf, 512, "Last leak repeated %lu time%s\n", leak_count, (leak_count>1?"s":""));
 				}
 #	if defined(PHP_WIN32)
-				OutputDebugString(memory_leak_buf);
+				if (IsDebuggerPresent()) {
+					OutputDebugString(memory_leak_buf);
+				} else {
+					fprintf(stderr, "%s", memory_leak_buf);
+				}
 #	else
 				fprintf(stderr, "%s", memory_leak_buf);
 #	endif
@@ -1695,7 +1699,11 @@ static ZEND_COLD void php_message_handler_for_zend(zend_long message, const void
 
 				snprintf(memory_leak_buf, 512, "=== Total %d memory leaks detected ===\n", *((uint32_t *) data));
 #	if defined(PHP_WIN32)
-				OutputDebugString(memory_leak_buf);
+				if (IsDebuggerPresent()) {
+					OutputDebugString(memory_leak_buf);
+				} else {
+					fprintf(stderr, "%s", memory_leak_buf);
+				}
 #	else
 				fprintf(stderr, "%s", memory_leak_buf);
 #	endif
@@ -1718,7 +1726,11 @@ static ZEND_COLD void php_message_handler_for_zend(zend_long message, const void
 					snprintf(memory_leak_buf, sizeof(memory_leak_buf), "[null]  Script:  '%s'\n", SAFE_FILENAME(SG(request_info).path_translated));
 				}
 #	if defined(PHP_WIN32)
-				OutputDebugString(memory_leak_buf);
+				if (IsDebuggerPresent()) {
+					OutputDebugString(memory_leak_buf);
+				} else {
+					fprintf(stderr, "%s", memory_leak_buf);
+				}
 #	else
 				fprintf(stderr, "%s", memory_leak_buf);
 #	endif