Don't compile S_env_alloc() when not used

RT #133360

I recently added S_env_alloc() as a helper function for
Perl_my_setenv(); but it's not needed on all platforms, so #ifdef it to
only be compiled on platforms where its needed.

Avoids a compiler warning.

1 files changed, 12 insertions, 8 deletions

diff --git a/util.c b/util.c
index 9d3f5ba0f1..37a71a1a81 100644
--- a/util.c
+++ b/util.c
@@ -2065,10 +2065,19 @@ Perl_new_warnings_bitfield(pTHX_ STRLEN *buffer, const char *const bits,
 #ifdef USE_ENVIRON_ARRAY
 /* NB: VMS' my_setenv() is in vms.c */
 
+/* Configure doesn't test for HAS_SETENV yet, so decide based on platform.
+ * For Solaris, setenv() and unsetenv() were introduced in Solaris 9, so
+ * testing for HAS UNSETENV is sufficient.
+ */
+#  if defined(__CYGWIN__)|| defined(__SYMBIAN32__) || defined(__riscos__) || (defined(__sun) && defined(HAS_UNSETENV)) || defined(PERL_DARWIN)
+#    define MY_HAS_SETENV
+#  endif
+
 /* small wrapper for use by Perl_my_setenv that mallocs, or reallocs if
  * 'current' is non-null, with up to three sizes that are added together.
  * It handles integer overflow.
  */
+#  ifndef MY_HAS_SETENV
 static char *
 S_env_alloc(void *current, Size_t l1, Size_t l2, Size_t l3, Size_t size)
 {
@@ -2093,6 +2102,7 @@ S_env_alloc(void *current, Size_t l1, Size_t l2, Size_t l3, Size_t size)
   panic:
     croak_memory_wrap();
 }
+#  endif
 
 
 #  if !defined(WIN32) && !defined(NETWARE)
@@ -2174,13 +2184,7 @@ Perl_my_setenv(pTHX_ const char *nam, const char *val)
 
 #    endif /* !PERL_USE_SAFE_PUTENV */
 
-    /* This next branch should only be called #if defined(HAS_SETENV), but
-       Configure doesn't test for that yet.  For Solaris, setenv() and
-       unsetenv() were introduced in Solaris 9, so testing for HAS
-       UNSETENV is sufficient.
-    */
-#    if defined(__CYGWIN__)|| defined(__SYMBIAN32__) || defined(__riscos__) || (defined(__sun) && defined(HAS_UNSETENV)) || defined(PERL_DARWIN)
-
+#    ifdef MY_HAS_SETENV
 #      if defined(HAS_UNSETENV)
         if (val == NULL) {
             (void)unsetenv(nam);
@@ -2218,7 +2222,7 @@ Perl_my_setenv(pTHX_ const char *nam, const char *val)
         my_setenv_format(new_env, nam, nlen, val, vlen);
         (void)putenv(new_env);
 
-#    endif /* __CYGWIN__ */
+#    endif /* MY_HAS_SETENV */
 
 #    ifndef PERL_USE_SAFE_PUTENV
     }