diff --git a/configure.ac b/configure.ac
index c2886439afa..9516b53f477 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1610,6 +1610,7 @@ PHP_ADD_SOURCES(TSRM, TSRM.c, -DZEND_ENABLE_STATIC_TSRMLS_CACHE=1)
 
 PHP_ADD_SOURCES(main, main.c snprintf.c spprintf.c \
        fopen_wrappers.c alloca.c  php_scandir.c \
+       php_ini_builder.c \
        php_ini.c SAPI.c rfc1867.c php_content_types.c strlcpy.c \
        strlcat.c explicit_bzero.c reentrancy.c php_variables.c php_ticks.c \
        network.c php_open_temporary_file.c \
diff --git a/main/php_ini_builder.c b/main/php_ini_builder.c
new file mode 100644
index 00000000000..d214a340343
--- /dev/null
+++ b/main/php_ini_builder.c
@@ -0,0 +1,82 @@
+/*
+   +----------------------------------------------------------------------+
+   | Copyright (c) The PHP Group                                          |
+   +----------------------------------------------------------------------+
+   | This source file is subject to version 3.01 of the PHP license,      |
+   | that is bundled with this package in the file LICENSE, and is        |
+   | available through the world-wide-web at the following url:           |
+   | https://www.php.net/license/3_01.txt                                 |
+   | If you did not receive a copy of the PHP license and are unable to   |
+   | obtain it through the world-wide-web, please send a note to          |
+   | license@php.net so we can mail you a copy immediately.               |
+   +----------------------------------------------------------------------+
+   | Authors: Max Kellermann <max.kellermann@ionos.com>                   |
+   +----------------------------------------------------------------------+
+*/
+
+#include "php_ini_builder.h"
+
+#include <ctype.h>
+#include <string.h>
+
+PHPAPI void php_ini_builder_prepend(struct php_ini_builder *b, const char *src, size_t length)
+{
+	php_ini_builder_realloc(b, length);
+	if (b->length > 0)
+		memmove(b->value + length, b->value, b->length);
+	memcpy(b->value, src, length);
+	b->length += length;
+}
+
+PHPAPI void php_ini_builder_unquoted(struct php_ini_builder *b, const char *name, size_t name_length, const char *value, size_t value_length)
+{
+	php_ini_builder_realloc(b, name_length + 1 + value_length + 1);
+
+	memcpy(b->value + b->length, name, name_length);
+	b->length += name_length;
+
+	b->value[b->length++] = '=';
+
+	memcpy(b->value + b->length, value, value_length);
+	b->length += value_length;
+
+	b->value[b->length++] = '\n';
+}
+
+PHPAPI void php_ini_builder_quoted(struct php_ini_builder *b, const char *name, size_t name_length, const char *value, size_t value_length)
+{
+	php_ini_builder_realloc(b, name_length + 2 + value_length + 2);
+
+	memcpy(b->value + b->length, name, name_length);
+	b->length += name_length;
+
+	b->value[b->length++] = '=';
+	b->value[b->length++] = '"';
+
+	memcpy(b->value + b->length, value, value_length);
+	b->length += value_length;
+
+	b->value[b->length++] = '"';
+	b->value[b->length++] = '\n';
+}
+
+PHPAPI void php_ini_builder_define(struct php_ini_builder *b, const char *arg)
+{
+	const size_t len = strlen(arg);
+	const char *val = strchr(arg, '=');
+
+	if (val != NULL) {
+		val++;
+		if (!isalnum(*val) && *val != '"' && *val != '\'' && *val != '\0') {
+			php_ini_builder_quoted(b, arg, val - arg - 1, val, arg + len - val);
+		} else {
+			php_ini_builder_realloc(b, len + strlen("\n"));
+			memcpy(b->value + b->length, arg, len);
+			b->length += len;
+			b->value[b->length++] = '\n';
+		}
+	} else {
+		php_ini_builder_unquoted(b, arg, len, "1", 1);
+	}
+}
+
diff --git a/main/php_ini_builder.h b/main/php_ini_builder.h
new file mode 100644
index 00000000000..7f5be81c10a
--- /dev/null
+++ b/main/php_ini_builder.h
@@ -0,0 +1,95 @@
+/*
+   +----------------------------------------------------------------------+
+   | Copyright (c) The PHP Group                                          |
+   +----------------------------------------------------------------------+
+   | This source file is subject to version 3.01 of the PHP license,      |
+   | that is bundled with this package in the file LICENSE, and is        |
+   | available through the world-wide-web at the following url:           |
+   | https://www.php.net/license/3_01.txt                                 |
+   | If you did not receive a copy of the PHP license and are unable to   |
+   | obtain it through the world-wide-web, please send a note to          |
+   | license@php.net so we can mail you a copy immediately.               |
+   +----------------------------------------------------------------------+
+   | Authors: Max Kellermann <max.kellermann@ionos.com>                   |
+   +----------------------------------------------------------------------+
+*/
+
+#ifndef PHP_INI_BUILDER_H
+#define PHP_INI_BUILDER_H
+
+#include "php.h"
+
+/**
+ * A class which helps with constructing INI entries from the command
+ * line.
+ */
+struct php_ini_builder {
+	char *value;
+	size_t length;
+};
+
+BEGIN_EXTERN_C()
+
+static inline void php_ini_builder_init(struct php_ini_builder *b)
+{
+	b->value = NULL;
+	b->length = 0;
+}
+
+static inline void php_ini_builder_deinit(struct php_ini_builder *b)
+{
+	free(b->value);
+}
+
+/**
+ * Null-terminate the buffer and return it.
+ */
+static inline char *php_ini_builder_finish(struct php_ini_builder *b)
+{
+	if (b->value != NULL) {
+		/* null-terminate the string */
+		b->value[b->length] = '\0';
+	}
+
+	return b->value;
+}
+
+/**
+ * Make room for more data.
+ *
+ * @param delta the number of bytes to be appended
+ */
+static inline void php_ini_builder_realloc(struct php_ini_builder *b, size_t delta)
+{
+	/* reserve enough space for the null terminator */
+	b->value = realloc(b->value, b->length + delta + 1);
+}
+
+/**
+ * Prepend a string.
+ *
+ * @param src the source string
+ * @param length the size of the source string
+ */
+PHPAPI void php_ini_builder_prepend(struct php_ini_builder *b, const char *src, size_t length);
+
+#define php_ini_builder_prepend_literal(b, l) php_ini_builder_prepend(b, l, strlen(l))
+
+/**
+ * Append an unquoted name/value pair.
+ */
+PHPAPI void php_ini_builder_unquoted(struct php_ini_builder *b, const char *name, size_t name_length, const char *value, size_t value_length);
+
+/**
+ * Append a quoted name/value pair.
+ */
+PHPAPI void php_ini_builder_quoted(struct php_ini_builder *b, const char *name, size_t name_length, const char *value, size_t value_length);
+
+/**
+ * Parse an INI entry from the command-line option "--define".
+ */
+PHPAPI void php_ini_builder_define(struct php_ini_builder *b, const char *arg);
+
+END_EXTERN_C()
+
+#endif
diff --git a/sapi/cgi/cgi_main.c b/sapi/cgi/cgi_main.c
index 7d5f444d1c5..ef6a62be73c 100644
--- a/sapi/cgi/cgi_main.c
+++ b/sapi/cgi/cgi_main.c
@@ -22,6 +22,7 @@
 #include "php.h"
 #include "php_globals.h"
 #include "php_variables.h"
+#include "php_ini_builder.h"
 #include "zend_modules.h"
 
 #include "SAPI.h"
@@ -1727,7 +1728,7 @@ int main(int argc, char *argv[])
 	int orig_optind = php_optind;
 	char *orig_optarg = php_optarg;
 	char *script_file = NULL;
-	size_t ini_entries_len = 0;
+	struct php_ini_builder ini_builder;
 	/* end of temporary locals */
 
 	int max_requests = 500;
@@ -1812,6 +1813,8 @@ int main(int argc, char *argv[])
 		free(decoded_query_string);
 	}
 
+	php_ini_builder_init(&ini_builder);
+
 	while (!skip_getopt && (c = php_getopt(argc, argv, OPTIONS, &php_optarg, &php_optind, 0, 2)) != -1) {
 		switch (c) {
 			case 'c':
@@ -1823,37 +1826,10 @@ int main(int argc, char *argv[])
 			case 'n':
 				cgi_sapi_module.php_ini_ignore = 1;
 				break;
-			case 'd': {
+			case 'd':
 				/* define ini entries on command line */
-				size_t len = strlen(php_optarg);
-				char *val;
-
-				if ((val = strchr(php_optarg, '='))) {
-					val++;
-					if (!isalnum(*val) && *val != '"' && *val != '\'' && *val != '\0') {
-						cgi_sapi_module.ini_entries = realloc(cgi_sapi_module.ini_entries, ini_entries_len + len + sizeof("\"\"\n\0"));
-						memcpy(cgi_sapi_module.ini_entries + ini_entries_len, php_optarg, (val - php_optarg));
-						ini_entries_len += (val - php_optarg);
-						memcpy(cgi_sapi_module.ini_entries + ini_entries_len, "\"", 1);
-						ini_entries_len++;
-						memcpy(cgi_sapi_module.ini_entries + ini_entries_len, val, len - (val - php_optarg));
-						ini_entries_len += len - (val - php_optarg);
-						memcpy(cgi_sapi_module.ini_entries + ini_entries_len, "\"\n\0", sizeof("\"\n\0"));
-						ini_entries_len += sizeof("\n\0\"") - 2;
-					} else {
-						cgi_sapi_module.ini_entries = realloc(cgi_sapi_module.ini_entries, ini_entries_len + len + sizeof("\n\0"));
-						memcpy(cgi_sapi_module.ini_entries + ini_entries_len, php_optarg, len);
-						memcpy(cgi_sapi_module.ini_entries + ini_entries_len + len, "\n\0", sizeof("\n\0"));
-						ini_entries_len += len + sizeof("\n\0") - 2;
-					}
-				} else {
-					cgi_sapi_module.ini_entries = realloc(cgi_sapi_module.ini_entries, ini_entries_len + len + sizeof("=1\n\0"));
-					memcpy(cgi_sapi_module.ini_entries + ini_entries_len, php_optarg, len);
-					memcpy(cgi_sapi_module.ini_entries + ini_entries_len + len, "=1\n\0", sizeof("=1\n\0"));
-					ini_entries_len += len + sizeof("=1\n\0") - 2;
-				}
+				php_ini_builder_define(&ini_builder, php_optarg);
 				break;
-			}
 			/* if we're started on command line, check to see if
 			 * we are being started as an 'external' fastcgi
 			 * server by accepting a bindpath parameter. */
@@ -1870,6 +1846,8 @@ int main(int argc, char *argv[])
 	php_optind = orig_optind;
 	php_optarg = orig_optarg;
 
+	cgi_sapi_module.ini_entries = php_ini_builder_finish(&ini_builder);
+
 	if (fastcgi || bindpath) {
 		/* Override SAPI callbacks */
 		cgi_sapi_module.ub_write     = sapi_fcgi_ub_write;
@@ -2619,9 +2597,7 @@ fastcgi_request_done:
 		if (cgi_sapi_module.php_ini_path_override) {
 			free(cgi_sapi_module.php_ini_path_override);
 		}
-		if (cgi_sapi_module.ini_entries) {
-			free(cgi_sapi_module.ini_entries);
-		}
+		php_ini_builder_deinit(&ini_builder);
 	} zend_catch {
 		exit_status = 255;
 	} zend_end_try();
diff --git a/sapi/cli/php_cli.c b/sapi/cli/php_cli.c
index fdd604cec53..97955eadd1f 100644
--- a/sapi/cli/php_cli.c
+++ b/sapi/cli/php_cli.c
@@ -21,6 +21,7 @@
 #include "php.h"
 #include "php_globals.h"
 #include "php_variables.h"
+#include "php_ini_builder.h"
 #include "zend_hash.h"
 #include "zend_modules.h"
 #include "zend_interfaces.h"
@@ -131,7 +132,7 @@ const char HARDCODED_INI[] =
 	"implicit_flush=1\n"
 	"output_buffering=0\n"
 	"max_execution_time=0\n"
-	"max_input_time=-1\n\0";
+	"max_input_time=-1\n";
 
 
 const opt_struct OPTIONS[] = {
@@ -1176,8 +1177,7 @@ int main(int argc, char *argv[])
 	char *php_optarg = NULL;
 	int php_optind = 1, use_extended_info = 0;
 	char *ini_path_override = NULL;
-	char *ini_entries = NULL;
-	size_t ini_entries_len = 0;
+	struct php_ini_builder ini_builder;
 	int ini_ignore = 0;
 	sapi_module_struct *sapi_module = &cli_sapi_module;
 
@@ -1239,6 +1239,8 @@ int main(int argc, char *argv[])
 	setmode(_fileno(stderr), O_BINARY);		/* make the stdio mode be binary */
 #endif
 
+	php_ini_builder_init(&ini_builder);
+
 	while ((c = php_getopt(argc, argv, OPTIONS, &php_optarg, &php_optind, 1, 2))!=-1) {
 		switch (c) {
 			case 'c':
@@ -1250,37 +1252,10 @@ int main(int argc, char *argv[])
 			case 'n':
 				ini_ignore = 1;
 				break;
-			case 'd': {
+			case 'd':
 				/* define ini entries on command line */
-				size_t len = strlen(php_optarg);
-				char *val;
-
-				if ((val = strchr(php_optarg, '='))) {
-					val++;
-					if (!isalnum(*val) && *val != '"' && *val != '\'' && *val != '\0') {
-						ini_entries = realloc(ini_entries, ini_entries_len + len + sizeof("\"\"\n\0"));
-						memcpy(ini_entries + ini_entries_len, php_optarg, (val - php_optarg));
-						ini_entries_len += (val - php_optarg);
-						memcpy(ini_entries + ini_entries_len, "\"", 1);
-						ini_entries_len++;
-						memcpy(ini_entries + ini_entries_len, val, len - (val - php_optarg));
-						ini_entries_len += len - (val - php_optarg);
-						memcpy(ini_entries + ini_entries_len, "\"\n\0", sizeof("\"\n\0"));
-						ini_entries_len += sizeof("\n\0\"") - 2;
-					} else {
-						ini_entries = realloc(ini_entries, ini_entries_len + len + sizeof("\n\0"));
-						memcpy(ini_entries + ini_entries_len, php_optarg, len);
-						memcpy(ini_entries + ini_entries_len + len, "\n\0", sizeof("\n\0"));
-						ini_entries_len += len + sizeof("\n\0") - 2;
-					}
-				} else {
-					ini_entries = realloc(ini_entries, ini_entries_len + len + sizeof("=1\n\0"));
-					memcpy(ini_entries + ini_entries_len, php_optarg, len);
-					memcpy(ini_entries + ini_entries_len + len, "=1\n\0", sizeof("=1\n\0"));
-					ini_entries_len += len + sizeof("=1\n\0") - 2;
-				}
+				php_ini_builder_define(&ini_builder, php_optarg);
 				break;
-			}
 #ifndef PHP_CLI_WIN32_NO_CONSOLE
 			case 'S':
 				sapi_module = &cli_server_sapi_module;
@@ -1317,18 +1292,10 @@ exit_loop:
 	sapi_module->executable_location = argv[0];
 
 	if (sapi_module == &cli_sapi_module) {
-		if (ini_entries) {
-			ini_entries = realloc(ini_entries, ini_entries_len + sizeof(HARDCODED_INI));
-			memmove(ini_entries + sizeof(HARDCODED_INI) - 2, ini_entries, ini_entries_len + 1);
-			memcpy(ini_entries, HARDCODED_INI, sizeof(HARDCODED_INI) - 2);
-		} else {
-			ini_entries = malloc(sizeof(HARDCODED_INI));
-			memcpy(ini_entries, HARDCODED_INI, sizeof(HARDCODED_INI));
-		}
-		ini_entries_len += sizeof(HARDCODED_INI) - 2;
+		php_ini_builder_prepend_literal(&ini_builder, HARDCODED_INI);
 	}
 
-	sapi_module->ini_entries = ini_entries;
+	sapi_module->ini_entries = php_ini_builder_finish(&ini_builder);
 
 	/* startup after we get the above ini override se we get things right */
 	if (sapi_module->startup(sapi_module) == FAILURE) {
@@ -1375,9 +1342,7 @@ out:
 	if (ini_path_override) {
 		free(ini_path_override);
 	}
-	if (ini_entries) {
-		free(ini_entries);
-	}
+	php_ini_builder_deinit(&ini_builder);
 	if (module_started) {
 		php_module_shutdown();
 	}
diff --git a/sapi/fpm/fpm/fpm_main.c b/sapi/fpm/fpm/fpm_main.c
index 657ff72b673..fe8195d1a8d 100644
--- a/sapi/fpm/fpm/fpm_main.c
+++ b/sapi/fpm/fpm/fpm_main.c
@@ -22,6 +22,7 @@
 #include "php.h"
 #include "php_globals.h"
 #include "php_variables.h"
+#include "php_ini_builder.h"
 #include "zend_modules.h"
 #include "php.h"
 #include "zend_ini_scanner.h"
@@ -1517,7 +1518,7 @@ int main(int argc, char *argv[])
 	/* temporary locals */
 	int orig_optind = php_optind;
 	char *orig_optarg = php_optarg;
-	int ini_entries_len = 0;
+	struct php_ini_builder ini_builder;
 	/* end of temporary locals */
 
 	int max_requests = 0;
@@ -1567,6 +1568,8 @@ int main(int argc, char *argv[])
 
 	fcgi_init();
 
+	php_ini_builder_init(&ini_builder);
+
 	while ((c = php_getopt(argc, argv, OPTIONS, &php_optarg, &php_optind, 0, 2)) != -1) {
 		switch (c) {
 			case 'c':
@@ -1580,37 +1583,10 @@ int main(int argc, char *argv[])
 				cgi_sapi_module.php_ini_ignore = 1;
 				break;
 
-			case 'd': {
+			case 'd':
 				/* define ini entries on command line */
-				int len = strlen(php_optarg);
-				char *val;
-
-				if ((val = strchr(php_optarg, '='))) {
-					val++;
-					if (!isalnum(*val) && *val != '"' && *val != '\'' && *val != '\0') {
-						cgi_sapi_module.ini_entries = realloc(cgi_sapi_module.ini_entries, ini_entries_len + len + sizeof("\"\"\n\0"));
-						memcpy(cgi_sapi_module.ini_entries + ini_entries_len, php_optarg, (val - php_optarg));
-						ini_entries_len += (val - php_optarg);
-						memcpy(cgi_sapi_module.ini_entries + ini_entries_len, "\"", 1);
-						ini_entries_len++;
-						memcpy(cgi_sapi_module.ini_entries + ini_entries_len, val, len - (val - php_optarg));
-						ini_entries_len += len - (val - php_optarg);
-						memcpy(cgi_sapi_module.ini_entries + ini_entries_len, "\"\n\0", sizeof("\"\n\0"));
-						ini_entries_len += sizeof("\n\0\"") - 2;
-					} else {
-						cgi_sapi_module.ini_entries = realloc(cgi_sapi_module.ini_entries, ini_entries_len + len + sizeof("\n\0"));
-						memcpy(cgi_sapi_module.ini_entries + ini_entries_len, php_optarg, len);
-						memcpy(cgi_sapi_module.ini_entries + ini_entries_len + len, "\n\0", sizeof("\n\0"));
-						ini_entries_len += len + sizeof("\n\0") - 2;
-					}
-				} else {
-					cgi_sapi_module.ini_entries = realloc(cgi_sapi_module.ini_entries, ini_entries_len + len + sizeof("=1\n\0"));
-					memcpy(cgi_sapi_module.ini_entries + ini_entries_len, php_optarg, len);
-					memcpy(cgi_sapi_module.ini_entries + ini_entries_len + len, "=1\n\0", sizeof("=1\n\0"));
-					ini_entries_len += len + sizeof("=1\n\0") - 2;
-				}
+				php_ini_builder_define(&ini_builder, php_optarg);
 				break;
-			}
 
 			case 'y':
 				fpm_config = php_optarg;
@@ -1703,6 +1679,8 @@ int main(int argc, char *argv[])
 		}
 	}
 
+	cgi_sapi_module.ini_entries = php_ini_builder_finish(&ini_builder);
+
 	if (php_information) {
 		cgi_sapi_module.phpinfo_as_text = 1;
 		cgi_sapi_module.startup(&cgi_sapi_module);
@@ -1957,9 +1935,7 @@ fastcgi_request_done:
 		if (cgi_sapi_module.php_ini_path_override) {
 			free(cgi_sapi_module.php_ini_path_override);
 		}
-		if (cgi_sapi_module.ini_entries) {
-			free(cgi_sapi_module.ini_entries);
-		}
+		php_ini_builder_deinit(&ini_builder);
 	} zend_catch {
 		exit_status = FPM_EXIT_SOFTWARE;
 	} zend_end_try();
diff --git a/sapi/phpdbg/phpdbg.c b/sapi/phpdbg/phpdbg.c
index 42a2a9c0364..e8d796771f9 100644
--- a/sapi/phpdbg/phpdbg.c
+++ b/sapi/phpdbg/phpdbg.c
@@ -29,6 +29,7 @@
 #include "phpdbg_help.h"
 #include "phpdbg_arginfo.h"
 #include "zend_vm.h"
+#include "php_ini_builder.h"
 
 #include "ext/standard/basic_functions.h"
 
@@ -995,7 +996,7 @@ const char phpdbg_ini_hardcoded[] =
 "max_execution_time=0\n"
 "max_input_time=-1\n"
 "error_log=\n"
-"output_buffering=off\n\0";
+"output_buffering=off\n";
 
 static void phpdbg_welcome(bool cleaning) /* {{{ */
 {
@@ -1122,8 +1123,7 @@ int main(int argc, char **argv) /* {{{ */
 {
 	sapi_module_struct *phpdbg = &phpdbg_sapi_module;
 	char *sapi_name;
-	char *ini_entries;
-	int   ini_entries_len;
+	struct php_ini_builder ini_builder;
 	char **zend_extensions = NULL;
 	zend_ulong zend_extensions_len = 0L;
 	bool ini_ignore;
@@ -1174,8 +1174,7 @@ phpdbg_main:
 
 	zend_signal_startup();
 
-	ini_entries = NULL;
-	ini_entries_len = 0;
+	php_ini_builder_init(&ini_builder);
 	ini_ignore = 0;
 	ini_override = NULL;
 	zend_extensions = NULL;
@@ -1210,35 +1209,10 @@ phpdbg_main:
 				}
 				ini_override = strdup(php_optarg);
 				break;
-			case 'd': {
-				int len = strlen(php_optarg);
-				char *val;
-
-				if ((val = strchr(php_optarg, '='))) {
-				  val++;
-				  if (!isalnum(*val) && *val != '"' && *val != '\'' && *val != '\0') {
-					  ini_entries = realloc(ini_entries, ini_entries_len + len + sizeof("\"\"\n\0"));
-					  memcpy(ini_entries + ini_entries_len, php_optarg, (val - php_optarg));
-					  ini_entries_len += (val - php_optarg);
-					  memcpy(ini_entries + ini_entries_len, "\"", 1);
-					  ini_entries_len++;
-					  memcpy(ini_entries + ini_entries_len, val, len - (val - php_optarg));
-					  ini_entries_len += len - (val - php_optarg);
-					  memcpy(ini_entries + ini_entries_len, "\"\n\0", sizeof("\"\n\0"));
-					  ini_entries_len += sizeof("\n\0\"") - 2;
-				  } else {
-					  ini_entries = realloc(ini_entries, ini_entries_len + len + sizeof("\n\0"));
-					  memcpy(ini_entries + ini_entries_len, php_optarg, len);
-					  memcpy(ini_entries + ini_entries_len + len, "\n\0", sizeof("\n\0"));
-					  ini_entries_len += len + sizeof("\n\0") - 2;
-				  }
-				} else {
-				  ini_entries = realloc(ini_entries, ini_entries_len + len + sizeof("=1\n\0"));
-				  memcpy(ini_entries + ini_entries_len, php_optarg, len);
-				  memcpy(ini_entries + ini_entries_len + len, "=1\n\0", sizeof("=1\n\0"));
-				  ini_entries_len += len + sizeof("=1\n\0") - 2;
-				}
-			} break;
+			case 'd':
+				/* define ini entries on command line */
+				php_ini_builder_define(&ini_builder, php_optarg);
+				break;
 
 			case 'z':
 				zend_extensions_len++;
@@ -1339,15 +1313,7 @@ phpdbg_main:
 	phpdbg->php_ini_ignore = ini_ignore;
 	phpdbg->php_ini_path_override = ini_override;
 
-	if (ini_entries) {
-		ini_entries = realloc(ini_entries, ini_entries_len + sizeof(phpdbg_ini_hardcoded));
-		memmove(ini_entries + sizeof(phpdbg_ini_hardcoded) - 2, ini_entries, ini_entries_len + 1);
-		memcpy(ini_entries, phpdbg_ini_hardcoded, sizeof(phpdbg_ini_hardcoded) - 2);
-	} else {
-		ini_entries = malloc(sizeof(phpdbg_ini_hardcoded));
-		memcpy(ini_entries, phpdbg_ini_hardcoded, sizeof(phpdbg_ini_hardcoded));
-	}
-	ini_entries_len += sizeof(phpdbg_ini_hardcoded) - 2;
+	php_ini_builder_prepend_literal(&ini_builder, phpdbg_ini_hardcoded);
 
 	if (zend_extensions_len) {
 		zend_ulong zend_extension = 0L;
@@ -1356,13 +1322,7 @@ phpdbg_main:
 			const char *ze = zend_extensions[zend_extension];
 			size_t ze_len = strlen(ze);
 
-			ini_entries = realloc(
-				ini_entries, ini_entries_len + (ze_len + (sizeof("zend_extension=\n"))));
-			memcpy(&ini_entries[ini_entries_len], "zend_extension=", (sizeof("zend_extension=\n")-1));
-			ini_entries_len += (sizeof("zend_extension=")-1);
-			memcpy(&ini_entries[ini_entries_len], ze, ze_len);
-			ini_entries_len += ze_len;
-			memcpy(&ini_entries[ini_entries_len], "\n", (sizeof("\n") - 1));
+			php_ini_builder_unquoted(&ini_builder, "zend_extension", strlen("zend_extension"), ze, ze_len);
 
 			free(zend_extensions[zend_extension]);
 			zend_extension++;
@@ -1371,7 +1331,7 @@ phpdbg_main:
 		free(zend_extensions);
 	}
 
-	phpdbg->ini_entries = ini_entries;
+	phpdbg->ini_entries = php_ini_builder_finish(&ini_builder);
 
 	ZEND_INIT_MODULE_GLOBALS(phpdbg, php_phpdbg_globals_ctor, NULL);
 
@@ -1421,9 +1381,7 @@ phpdbg_main:
 			}
 			sapi_deactivate();
 			sapi_shutdown();
-			if (ini_entries) {
-				free(ini_entries);
-			}
+			php_ini_builder_deinit(&ini_builder);
 			if (ini_override) {
 				free(ini_override);
 			}
@@ -1698,9 +1656,7 @@ phpdbg_out:
 			efree(SG(request_info).argv);
 		}
 
-		if (ini_entries) {
-			free(ini_entries);
-		}
+		php_ini_builder_deinit(&ini_builder);
 
 		if (ini_override) {
 			free(ini_override);
diff --git a/win32/build/config.w32 b/win32/build/config.w32
index b28a97672e3..9f281390c43 100644
--- a/win32/build/config.w32
+++ b/win32/build/config.w32
@@ -261,6 +261,7 @@ if (VS_TOOLSET && VCVERS >= 1914) {
 //AC_DEFINE('ZEND_DVAL_TO_LVAL_CAST_OK', 1);
 
 ADD_SOURCES("main", "main.c snprintf.c spprintf.c getopt.c fopen_wrappers.c \
+	php_ini_builder.c \
 	php_scandir.c php_ini.c SAPI.c rfc1867.c php_content_types.c strlcpy.c \
 	strlcat.c reentrancy.c php_variables.c php_ticks.c network.c \
 	php_open_temporary_file.c output.c internal_functions.c \