Fix PerlEnv_putenv threaded compilation on Windows

A second compilation of a workspace would fail.  The first one would
succeed because miniperl was being used, which isn't threaded.

1 files changed, 19 insertions, 0 deletions

diff --git a/inline.h b/inline.h
index 38de751bd6..06a773d2c3 100644
--- a/inline.h
+++ b/inline.h
@@ -281,6 +281,25 @@ S_strip_spaces(pTHX_ const char * orig, STRLEN * const len)
 }
 #endif
 
+/* ------------------------------- iperlsys.h ------------------------------- */
+#if ! defined(PERL_IMPLICIT_SYS) && defined(USE_ITHREADS)
+
+/* Otherwise this function is implemented as macros in iperlsys.h */
+
+PERL_STATIC_INLINE bool
+Perl_PerlEnv_putenv(pTHX_ char * str)
+{
+    PERL_ARGS_ASSERT_PERLENV_PUTENV;
+
+    ENV_LOCK;
+    bool retval = putenv(str);
+    ENV_UNLOCK;
+
+    return retval;
+}
+
+#endif
+
 /* ------------------------------- mg.h ------------------------------- */
 
 #if defined(PERL_CORE) || defined(PERL_EXT)