Remove broken AC_CHECK_DECLS(getenv).

We were testing #ifndef HAVE_DECL_GETENV, which was always false.
Thus, it is safe to assume that the test never triggered, and
the entire #ifndef...#endif block can be removed.

3 files changed, 7 insertions, 5 deletions

diff --git a/NEWS b/NEWS
index bd92702b..79973449 100644
--- a/NEWS
+++ b/NEWS
@@ -91,6 +91,12 @@ fetchmail-6.4.3 (WIP)
   with OpenSSL lacks TLS v1.3 support.
 * If the trust anchor is missing, fetchmail refers the user to README.SSL.
 
+## INTERNAL CHANGES:
+* The AC_DECLS(getenv) check was removed, its only user was broken and not 
+  accounting for that AC_DECLS always defines HAVE_DECL_... to 0 or 1, so
+  fetchmail never declared a missing getenv() symbol (it was testing with 
+  #ifdef).  Remove the backup declaration. getenv is mandated by SUSv2 anyways.
+
 fetchmail-6.4.2 (released 2020-02-14, 27473 LoC):
 
 ## BREAKING CHANGES:
diff --git a/configure.ac b/configure.ac
index 4990fe49..ccca38d6 100644
--- a/configure.ac
+++ b/configure.ac
@@ -180,7 +180,7 @@ AC_CHECK_FUNCS(tcsetattr stty setsid geteuid seteuid dnl
   atexit inet_aton strftime setrlimit socketpair dnl
   sigaction strdup setlocale)
 
-AC_CHECK_DECLS([strerror,getenv])
+AC_CHECK_DECLS([strerror])
 dnl INET6 is used by KAME/getnameinfo
 AC_CACHE_CHECK(for AF_INET6/PF_INET6,ac_cv_inet6,
 AC_COMPILE_IFELSE([
diff --git a/env.c b/env.c
index a26cf908..4ee0d23f 100644
--- a/env.c
+++ b/env.c
@@ -31,10 +31,6 @@
 #endif
 #include <limits.h>
 
-#ifndef HAVE_DECL_GETENV
-extern char *getenv(const char *);	/* needed on sysV68 R3V7.1. */
-#endif
-
 void envquery(int argc, char **argv)
 /* set up basic stuff from the environment (including the rc file name) */
 {