Reword Windows makefile comments to explain the "help" logic about USE_MULTI

There is logic to auto-enable USE_MULTI if either USE_ITHREADS or USE_IMP_SYS
(which both require USE_MULTI) are enabled, but this is not mentioned in
the comments. Explain it so that users don't get confused when trying to
disable USE_MULTI.

Reported in [perl #121494].

diff --git a/win32/Makefile b/win32/Makefile
index 5991a00..a0a3b4e 100644 (file)
--- a/win32/Makefile
+++ b/win32/Makefile
@@ -59,22 +59,23 @@ INST_TOP    = $(INST_DRV)\perl
 #USE_SITECUST  = define
 
 #
-# uncomment to enable multiple interpreters.  This is need for fork()
-# emulation and for thread support.
+# uncomment to enable multiple interpreters.  This is needed for fork()
+# emulation and for thread support, and is auto-enabled by USE_IMP_SYS
+# and USE_ITHREADS below.
 #
 USE_MULTI      = define
 
 #
-# Beginnings of interpreter cloning/threads; now reasonably complete.
-# This should be enabled to get the fork() emulation.  This needs
-# USE_MULTI as well.
+# Interpreter cloning/threads; now reasonably complete.
+# This should be enabled to get the fork() emulation.  This needs (and
+# will auto-enable) USE_MULTI above.
 #
 USE_ITHREADS   = define
 
 #
 # uncomment to enable the implicit "host" layer for all system calls
-# made by perl.  This needs USE_MULTI above.  This is also needed to
-# get fork().
+# made by perl.  This is also needed to get fork().  This needs (and
+# will auto-enable) USE_MULTI above.
 #
 USE_IMP_SYS    = define
 

diff --git a/win32/makefile.mk b/win32/makefile.mk
index 269f4b7..c11a7a9 100644 (file)
--- a/win32/makefile.mk
+++ b/win32/makefile.mk
@@ -65,22 +65,23 @@ INST_TOP    *= $(INST_DRV)\perl
 #USE_SITECUST  *= define
 
 #
-# uncomment to enable multiple interpreters.  This is need for fork()
-# emulation and for thread support.
+# uncomment to enable multiple interpreters.  This is needed for fork()
+# emulation and for thread support, and is auto-enabled by USE_IMP_SYS
+# and USE_ITHREADS below.
 #
 USE_MULTI      *= define
 
 #
 # Interpreter cloning/threads; now reasonably complete.
-# This should be enabled to get the fork() emulation.  
-# This needs USE_MULTI above.
+# This should be enabled to get the fork() emulation.  This needs (and
+# will auto-enable) USE_MULTI above.
 #
 USE_ITHREADS   *= define
 
 #
 # uncomment to enable the implicit "host" layer for all system calls
-# made by perl.  This needs USE_MULTI above.  
-# This is also needed to get fork().
+# made by perl.  This is also needed to get fork().  This needs (and
+# will auto-enable) USE_MULTI above.
 #
 USE_IMP_SYS    *= define