[php-src] Issue #13154: ./configure ignores CFLAGS in master

Issue: https://github.com/php/php-src/issues/13154 Author: divinity76 ### Description In the PHP8.1 branch (and iirc all the way back to the PHP5.6 branch) this works: ```bash CFLAGS='-s -Os -ng -march=native' ./configure ``` files would be compiled with those flags, here's a snippet from a 8.1 branch compilation: ``` /bin/sh /hans_temp/php/php-src/libtool --silent --preserve-dup-deps --tag CC --mode=compile cc -Isapi/phpdbg/ -I/hans_temp/php/php-src/sapi/phpdbg/ -I/hans_temp/php/php-src/include -I/hans_temp/php/php-src/main -I/hans_temp/php/php-src -I/hans_temp/php/php-src/ext/date/lib -I/usr/include/libxml2 -I/hans_temp/php/php-src/TSRM -I/hans_temp/php/php-src/Zend -fno-common -Wformat-truncation -Wlogical-op -Wduplicated-cond -Wno-clobbered -Wall -Wextra -Wno-strict-aliasing -Wno-unused-parameter -Wno-sign-compare -s -Os -g0 -fvisibility=hidden -Wimplicit-fallthrough=1 -DZEND_SIGNALS -D_GNU_SOURCE -DZEND_ENABLE_STATIC_TSRMLS_CACHE=1 -c /hans_temp/php/php-src/sapi/phpdbg/phpdbg_io.c -o sapi/phpdbg/phpdbg_io.lo -MMD -MF sapi/phpdbg/phpdbg_io.dep -MT sapi/phpdbg/phpdbg_io.lo ``` but in current master, it does not work, configure ignores CFLAGS, here's a snippet from current master build: ``` /bin/bash /home/hans/projects/php-src/libtool --silent --preserve-dup-deps --tag=CC --mode=compile cc -Isapi/phpdbg/ -I/home/hans/projects/php-src/sapi/phpdbg/ -I/home/hans/projects/php-src/include -I/home/hans/projects/php-src/main -I/home/hans/projects/php-src -I/home/hans/projects/php-src/ext/date/lib -I/usr/include/x86_64-linux-gnu -I/home/hans/projects/php-src/TSRM -I/home/hans/projects/php-src/Zend -D_GNU_SOURCE -fno-common -Wstrict-prototypes -Wformat-truncation -Wlogical-op -Wduplicated-cond -Wno-clobbered -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -g -O2 -fvisibility=hidden -Wimplicit-fallthrough=1 -DZEND_SIGNALS -D_GNU_SOURCE -DZEND_ENABLE_STATIC_TSRMLS_CACHE=1 -pthread -c /home/hans/projects/php-src/sapi/phpdbg/phpdbg_watch.c -o sapi/phpdbg/phpdbg_watch.lo -MMD -MF sapi/phpdbg/phpdbg_watch.dep -MT sapi/phpdbg/phpdbg_watch.lo ``` ### PHP Version c39a8631b7a4dea6a315dbf697388cca9f0bfa9c ### Operating System _No response_