new: clear CFLAGS in gcc and glibc

lfs/gcc-14.2.0.PKGBUILD

@@ -17,6 +17,9 @@ src_prepare() {
 }
 
 src_build() {
+  old_cflags="$CFLAGS"
+  unset CFLAGS
+
   mkdir -v build
   pushd build > /dev/null
   ../configure --prefix=/usr            \
@@ -30,6 +33,8 @@ src_build() {
                --disable-fixincludes    \
                --with-system-zlib
   make
+
+  export CFLAGS="$old_cflags"
   popd
 }
 
@@ -43,7 +48,7 @@ src_check() {
       -e '/GOTPCREL/d'              -i ../gcc/testsuite/gcc.target/i386/fentryname3.c
 
   chown -R leaf .
-  su leaf -c "PATH=$PATH make -k check"
+  env -u CFLAGS su leaf -c "PATH=$PATH make -k check"
   ../contrib/test_summary | grep -A7 Summ
   popd
 }

lfs/glibc-2.41.PKGBUILD

@@ -26,6 +26,9 @@ src_prepare() {
 }
 
 src_build() {
+  old_cflags="$CFLAGS"
+  unset CFLAGS
+
   mkdir -pv build
   cd build
   echo "rootsbindir=/usr/sbin" > configparms
@@ -36,6 +39,8 @@ src_build() {
                --disable-nscd                           \
                libc_cv_slibdir=/usr/lib
   make
+
+  export CFLAGS="$old_cflags"
 }
 
 _skip_test() {
@@ -46,10 +51,16 @@ _skip_test() {
 
 src_check() {
   _skip_test tst-lchmod io/Makefile
+
+  old_cflags="$CFLAGS"
+  unset CFLAGS
   make check
+  export CFLAGS="$old_cflags"
 }
 
 src_install() {
+  old_cflags="$CFLAGS"
+  unset CFLAGS
   cd "${srcdir}/build"
   install -d "${pkgdir}/etc"
   touch "${pkgdir}/etc/ld.so.conf"
@@ -110,6 +121,8 @@ src_install() {
   unset ZONEINFO
 
   install -m644 "${distdir}/${sources[3]}" "${pkgdir}/etc/ld.so.conf"
+
+  export CFLAGS="$old_cflags"
 }
 
 src_preinstall() {