make PERL_USE_SAFE_PUTENV the default and the only option

Now environ isn't owned by Perl and calling setenv/putenv in XS code
will no longer result in memory corruption.

Fixes #19399

5 files changed, 2 insertions, 29 deletions

diff --git a/hints/cygwin.sh b/hints/cygwin.sh
index 40edf5f6b1..9988b3eb48 100644
--- a/hints/cygwin.sh
+++ b/hints/cygwin.sh
@@ -31,7 +31,7 @@ test -z "$optimize" && optimize='-O3'
 man3ext='3pm'
 test -z "$use64bitint" && use64bitint='define'
 test -z "$useithreads" && useithreads='define'
-ccflags="$ccflags -DPERL_USE_SAFE_PUTENV -U__STRICT_ANSI__ -D_GNU_SOURCE"
+ccflags="$ccflags -U__STRICT_ANSI__ -D_GNU_SOURCE"
 # - otherwise i686-cygwin
 archname='cygwin'
 
diff --git a/hints/darwin.sh b/hints/darwin.sh
index ea521003c3..97a3ec59a9 100644
--- a/hints/darwin.sh
+++ b/hints/darwin.sh
@@ -509,16 +509,6 @@ esac
 # the problem.
 firstmakefile=GNUmakefile;
 
-# Parts of the system call setenv(), in particular in an atfork handler.
-# This causes problems when the child tries to clean up environ[], so
-# let libc manage environ[].
-cat >> config.over <<'EOOVER'
-if test "$d_unsetenv" = "$define" -a \
-    `expr "$ccflags" : '.*-DPERL_USE_SAFE_PUTENV'` -eq 0; then
-        ccflags="$ccflags -DPERL_USE_SAFE_PUTENV"
-fi
-EOOVER
-
 # if you use a newer toolchain before OS X 10.9 these functions may be
 # incorrectly detected, so disable them
 # OS X 10.10.x corresponds to kernel 14.x
diff --git a/hints/os390.sh b/hints/os390.sh
index 8995d8c353..56f247bfcf 100644
--- a/hints/os390.sh
+++ b/hints/os390.sh
@@ -63,8 +63,6 @@ myfirstchar=$(od -A n -N 1 -t x $me | xargs | tr [:lower:] [:upper:] | tr -d 0)
 if [ "${myfirstchar}" = "23" ]; then # 23 is '#' in ASCII
   unset ebcdic
   def_os390_cflags="$def_os390_cflags -qascii"
-  # ensure that 'safe' putenv is used and avoid direct environ manipulation
-  def_os390_defs="$def_os390_defs -DPERL_USE_SAFE_PUTENV";
 else
   ebcdic=true
 fi
diff --git a/hints/riscos.sh b/hints/riscos.sh
index e87e99ce14..2225f093cc 100644
--- a/hints/riscos.sh
+++ b/hints/riscos.sh
@@ -5,7 +5,7 @@
 
 cc='gcc'
 locincpth=""
-ccflags="-mpoke-function-name -DDYNAMIC_ENV_FETCH -DPERL_USE_SAFE_PUTENV"
+ccflags="-mpoke-function-name -DDYNAMIC_ENV_FETCH"
 prefix='/<Perl$Dir>'
 osname='riscos'
 libpth=' '
diff --git a/hints/solaris_2.sh b/hints/solaris_2.sh
index e50d9d8323..21bfc8756e 100644
--- a/hints/solaris_2.sh
+++ b/hints/solaris_2.sh
@@ -694,21 +694,6 @@ EOM
 esac
 EOCBU
 
-#
-# If unsetenv is available, use it in conjunction with PERL_USE_SAFE_PUTENV to
-# work around Sun bugid 6333830.  Both unsetenv and 6333830 only appear in
-# Solaris 10, so we don't need to probe explicitly for an OS version.  We have
-# to append this test to the end of config.over as it needs to run after
-# Configure has probed for unsetenv, and this hints file is processed before
-# that has happened.
-#
-cat >> config.over <<'EOOVER'
-if test "$d_unsetenv" = "$define" -a \
-    `expr "$ccflags" : '.*-DPERL_USE_SAFE_PUTENV'` -eq 0; then
-        ccflags="$ccflags -DPERL_USE_SAFE_PUTENV"
-fi
-EOOVER
-
 rm -f try.c try.o try a.out
 
 # If using C++, the Configure scan for dlopen() will fail in Solaris