diff --git a/configure.ac b/configure.ac
index 7f6455fdfc7af..f60b2a07c5616 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1426,19 +1426,23 @@ EXTRA_LDFLAGS_PROGRAM="$EXTRA_LDFLAGS_PROGRAM $PHP_LDFLAGS"
 
 UNAME=`uname -a | xargs`
 PHP_UNAME=${PHP_UNAME:-$UNAME}
-AC_DEFINE_UNQUOTED(PHP_UNAME,"$PHP_UNAME",[uname -a output])
+AC_DEFINE_UNQUOTED([PHP_UNAME], ["$PHP_UNAME"], [The 'uname -a' output.])
 PHP_OS=`uname | xargs`
-AC_DEFINE_UNQUOTED(PHP_OS,"$PHP_OS",[uname output])
+AC_DEFINE_UNQUOTED([PHP_OS], ["$PHP_OS"], [The 'uname' output.])
 PHP_BUILD_SYSTEM=${PHP_BUILD_SYSTEM:-$PHP_UNAME}
-AC_DEFINE_UNQUOTED(PHP_BUILD_SYSTEM,"$PHP_BUILD_SYSTEM",[builder uname output])
+AC_DEFINE_UNQUOTED([PHP_BUILD_SYSTEM], ["$PHP_BUILD_SYSTEM"],
+  [The system that PHP was built on.])
 if test -n "${PHP_BUILD_PROVIDER}"; then
-  AC_DEFINE_UNQUOTED(PHP_BUILD_PROVIDER,"$PHP_BUILD_PROVIDER",[build provider])
+  AC_DEFINE_UNQUOTED([PHP_BUILD_PROVIDER], ["$PHP_BUILD_PROVIDER"],
+    [The PHP build provider information.])
 fi
 if test -n "${PHP_BUILD_COMPILER}"; then
-  AC_DEFINE_UNQUOTED(PHP_BUILD_COMPILER,"$PHP_BUILD_COMPILER",[used compiler for build])
+  AC_DEFINE_UNQUOTED([PHP_BUILD_COMPILER], ["$PHP_BUILD_COMPILER"],
+    [The compiler used for the PHP build.])
 fi
 if test -n "${PHP_BUILD_ARCH}"; then
-  AC_DEFINE_UNQUOTED(PHP_BUILD_ARCH,"$PHP_BUILD_ARCH",[build architecture])
+  AC_DEFINE_UNQUOTED([PHP_BUILD_ARCH], ["$PHP_BUILD_ARCH"],
+    [The build architecture.])
 fi
 
 PHP_SUBST([PHP_FASTCGI_OBJS])
diff --git a/win32/build/confutils.js b/win32/build/confutils.js
index 4495ed73c04d2..2074b9a90d29e 100644
--- a/win32/build/confutils.js
+++ b/win32/build/confutils.js
@@ -132,10 +132,10 @@ extension_module_ptrs = "";
 	var wmiservice = GetObject("winmgmts:{impersonationLevel=impersonate}!\\\\.\\root\\cimv2");
 	var oss = wmiservice.ExecQuery("Select * from Win32_OperatingSystem");
 	var os = oss.ItemIndex(0);
-	AC_DEFINE("PHP_BUILD_SYSTEM", os.Caption + " [" + os.Version + "]", "Windows build system version");
+	AC_DEFINE("PHP_BUILD_SYSTEM", os.Caption + " [" + os.Version + "]", "The system that PHP was built on.");
 	var build_provider = WshShell.Environment("Process").Item("PHP_BUILD_PROVIDER");
 	if (build_provider) {
-		AC_DEFINE("PHP_BUILD_PROVIDER", build_provider);
+		AC_DEFINE("PHP_BUILD_PROVIDER", build_provider, "The PHP build provider information.");
 	}
 }());
 
@@ -2945,25 +2945,25 @@ function toolset_setup_compiler()
 
 			WARNING("Using unknown MSVC version " + tmp);
 
-			AC_DEFINE('PHP_BUILD_COMPILER', COMPILER_NAME_LONG, "Detected compiler version");
+			AC_DEFINE('PHP_BUILD_COMPILER', COMPILER_NAME_LONG, "The compiler used for the PHP build.");
 			DEFINE("PHP_COMPILER_SHORT", tmp);
 			AC_DEFINE('PHP_COMPILER_ID', tmp, "Compiler compatibility ID");
 		} else {
-			AC_DEFINE('PHP_BUILD_COMPILER', COMPILER_NAME_LONG, "Detected compiler version");
+			AC_DEFINE('PHP_BUILD_COMPILER', COMPILER_NAME_LONG, "The compiler used for the PHP build.");
 			DEFINE("PHP_COMPILER_SHORT", COMPILER_NAME_SHORT.toLowerCase());
 			AC_DEFINE('PHP_COMPILER_ID', COMPILER_NAME_SHORT.toUpperCase(), "Compiler compatibility ID");
 		}
 	} else if (CLANG_TOOLSET) {
 		CLANGVERS = COMPILER_NUMERIC_VERSION;
 
-		AC_DEFINE('PHP_BUILD_COMPILER', COMPILER_NAME_LONG, "Detected compiler version");
+		AC_DEFINE('PHP_BUILD_COMPILER', COMPILER_NAME_LONG, "The compiler used for the PHP build.");
 		DEFINE("PHP_COMPILER_SHORT", "clang");
 		AC_DEFINE('PHP_COMPILER_ID', "clang"); /* XXX something better were to write here */
 
 	} else if (ICC_TOOLSET) {
 		INTELVERS = COMPILER_NUMERIC_VERSION;
 
-		AC_DEFINE('PHP_BUILD_COMPILER', COMPILER_NAME_LONG, "Detected compiler version");
+		AC_DEFINE('PHP_BUILD_COMPILER', COMPILER_NAME_LONG, "The compiler used for the PHP build.");
 		DEFINE("PHP_COMPILER_SHORT", "icc");
 		AC_DEFINE('PHP_COMPILER_ID', "icc"); /* XXX something better were to write here */
 	}
@@ -3185,7 +3185,7 @@ function toolset_target_arch()
 function toolset_setup_arch()
 {
 	STDOUT.WriteLine("  Detected " + TARGET_ARCH + " compiler" + (TARGET_ARCH == HOST_ARCH ? "" : " (cross compile from " + HOST_ARCH + ")"));
-	AC_DEFINE('PHP_BUILD_ARCH', TARGET_ARCH, "Detected compiler architecture");
+	AC_DEFINE('PHP_BUILD_ARCH', TARGET_ARCH, "The build architecture.");
 	DEFINE("PHP_ARCHITECTURE", TARGET_ARCH);
 }