diff --git a/ext/date/php_date.c b/ext/date/php_date.c
index 1bf59ae5f9b24..6d8b765578b41 100644
--- a/ext/date/php_date.c
+++ b/ext/date/php_date.c
@@ -1302,20 +1302,20 @@ PHPAPI void php_strftime(INTERNAL_FUNCTION_PARAMETERS, bool gmt)
 	ta.tm_yday  = timelib_day_of_year(ts->y, ts->m, ts->d);
 	if (gmt) {
 		ta.tm_isdst = 0;
-#if HAVE_STRUCT_TM_TM_GMTOFF
+#ifdef HAVE_STRUCT_TM_TM_GMTOFF
 		ta.tm_gmtoff = 0;
 #endif
-#if HAVE_STRUCT_TM_TM_ZONE
+#ifdef HAVE_STRUCT_TM_TM_ZONE
 		ta.tm_zone = "GMT";
 #endif
 	} else {
 		offset = timelib_get_time_zone_info(timestamp, tzi);
 
 		ta.tm_isdst = offset->is_dst;
-#if HAVE_STRUCT_TM_TM_GMTOFF
+#ifdef HAVE_STRUCT_TM_TM_GMTOFF
 		ta.tm_gmtoff = offset->offset;
 #endif
-#if HAVE_STRUCT_TM_TM_ZONE
+#ifdef HAVE_STRUCT_TM_TM_ZONE
 		ta.tm_zone = offset->abbr;
 #endif
 	}
diff --git a/ext/iconv/iconv.c b/ext/iconv/iconv.c
index d2279d27bf769..78f48d84e96ad 100644
--- a/ext/iconv/iconv.c
+++ b/ext/iconv/iconv.c
@@ -58,7 +58,7 @@
 
 #ifdef PHP_ICONV_IMPL
 #define PHP_ICONV_IMPL_VALUE PHP_ICONV_IMPL
-#elif HAVE_LIBICONV
+#elif defined(HAVE_LIBICONV)
 #define PHP_ICONV_IMPL_VALUE "libiconv"
 #else
 #define PHP_ICONV_IMPL_VALUE "unknown"
diff --git a/ext/random/csprng.c b/ext/random/csprng.c
index 1bb31bffa20ff..429fe88a84201 100644
--- a/ext/random/csprng.c
+++ b/ext/random/csprng.c
@@ -52,7 +52,7 @@
 # endif
 #endif
 
-#if HAVE_COMMONCRYPTO_COMMONRANDOM_H
+#ifdef HAVE_COMMONCRYPTO_COMMONRANDOM_H
 # include <CommonCrypto/CommonCryptoError.h>
 # include <CommonCrypto/CommonRandom.h>
 #endif
@@ -71,7 +71,7 @@ PHPAPI zend_result php_random_bytes(void *bytes, size_t size, bool should_throw)
 		}
 		return FAILURE;
 	}
-#elif HAVE_COMMONCRYPTO_COMMONRANDOM_H
+#elif defined(HAVE_COMMONCRYPTO_COMMONRANDOM_H)
 	/*
 	 * Purposely prioritized upon arc4random_buf for modern macOs releases
 	 * arc4random api on this platform uses `ccrng_generate` which returns
diff --git a/ext/sockets/conversions.c b/ext/sockets/conversions.c
index cc0ae36ecb5e4..198ec02583edc 100644
--- a/ext/sockets/conversions.c
+++ b/ext/sockets/conversions.c
@@ -1261,7 +1261,7 @@ static void from_zval_write_ifindex(const zval *zv, char *uinteger, ser_context
 
 		str = zval_get_tmp_string((zval *) zv, &tmp_str);
 
-#if HAVE_IF_NAMETOINDEX
+#ifdef HAVE_IF_NAMETOINDEX
 		ret = if_nametoindex(ZSTR_VAL(str));
 		if (ret == 0) {
 			do_from_zval_err(ctx, "no interface with name \"%s\" could be found", ZSTR_VAL(str));
diff --git a/ext/sockets/multicast.c b/ext/sockets/multicast.c
index 1cfdf1e18d481..4d13b9e94ca3f 100644
--- a/ext/sockets/multicast.c
+++ b/ext/sockets/multicast.c
@@ -61,7 +61,7 @@ static int _php_source_op_to_ipv4_op(enum source_op sop);
 
 zend_result php_string_to_if_index(const char *val, unsigned *out)
 {
-#if HAVE_IF_NAMETOINDEX
+#ifdef HAVE_IF_NAMETOINDEX
 	unsigned int ind;
 
 	ind = if_nametoindex(val);
diff --git a/ext/sockets/php_sockets.h b/ext/sockets/php_sockets.h
index 42db7679522ed..d7a79714a2c91 100644
--- a/ext/sockets/php_sockets.h
+++ b/ext/sockets/php_sockets.h
@@ -24,7 +24,7 @@
 # include "config.h"
 #endif
 
-#if HAVE_SOCKETS
+#ifdef HAVE_SOCKETS
 
 #include <php.h>
 #ifdef PHP_WIN32
diff --git a/ext/sockets/sockets.c b/ext/sockets/sockets.c
index 1de50d9f88788..b532e942710fa 100644
--- a/ext/sockets/sockets.c
+++ b/ext/sockets/sockets.c
@@ -51,7 +51,7 @@
 # include <sys/uio.h>
 # define set_errno(a) (errno = a)
 # include "php_sockets.h"
-# if HAVE_IF_NAMETOINDEX
+# ifdef HAVE_IF_NAMETOINDEX
 #  include <net/if.h>
 # endif
 # if defined(HAVE_LINUX_SOCK_DIAG_H)
diff --git a/main/streams/cast.c b/main/streams/cast.c
index 238212c745ed4..d4a0b22899ddf 100644
--- a/main/streams/cast.c
+++ b/main/streams/cast.c
@@ -128,7 +128,7 @@ static int stream_cookie_closer(void *cookie)
 }
 #endif /* elif defined(HAVE_FOPENCOOKIE) */
 
-#if HAVE_FOPENCOOKIE
+#ifdef HAVE_FOPENCOOKIE
 static cookie_io_functions_t stream_cookie_functions =
 {
 	stream_cookie_reader, stream_cookie_writer,
@@ -220,7 +220,7 @@ PHPAPI int _php_stream_cast(php_stream *stream, int castas, void **ret, int show
 			goto exit_success;
 		}
 
-#if HAVE_FOPENCOOKIE
+#ifdef HAVE_FOPENCOOKIE
 		/* if just checking, say yes we can be a FILE*, but don't actually create it yet */
 		if (ret == NULL) {
 			goto exit_success;
diff --git a/main/streams/userspace.c b/main/streams/userspace.c
index 2a7380ce8f3a6..d765448d7a636 100644
--- a/main/streams/userspace.c
+++ b/main/streams/userspace.c
@@ -816,7 +816,7 @@ static int statbuf_from_array(zval *array, php_stream_statbuf *ssb)
 	STAT_PROP_ENTRY(nlink);
 	STAT_PROP_ENTRY(uid);
 	STAT_PROP_ENTRY(gid);
-#if HAVE_STRUCT_STAT_ST_RDEV
+#ifdef HAVE_STRUCT_STAT_ST_RDEV
 	STAT_PROP_ENTRY(rdev);
 #endif
 	STAT_PROP_ENTRY(size);
diff --git a/sapi/fuzzer/fuzzer-exif.c b/sapi/fuzzer/fuzzer-exif.c
index cb16bb90233a0..e35ee9af23e1e 100644
--- a/sapi/fuzzer/fuzzer-exif.c
+++ b/sapi/fuzzer/fuzzer-exif.c
@@ -31,7 +31,7 @@
 #include "fuzzer-sapi.h"
 
 int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
-#if HAVE_EXIF
+#ifdef HAVE_EXIF
 	php_stream *stream;
 	zval stream_zv;