protsym: don't refer to symbols excluded by config.

The protsym.c generated file refers to symbol variables
without regard for whether they actually exist.
Some symbol variables are defined in source files whose
object files are only linked in conditionally.

* genprotsym.txr: Update the logic to scan the Makefile
to determine which files are conditionally included, based on
what makefile flag, which is related to a preprocessor symbol.
Thus, with some hashes, for each symbolic variable we
subsequently scan, we know whether it came from a file that is
associated with a preprocessor symbol. We group the emitted
material accordingly, placing the conditionally existent
symbols into #if...#endif blocks.

1 files changed, 34 insertions, 6 deletions

diff --git a/genprotsym.txr b/genprotsym.txr
index 7d9f8c2a..b343ce04 100644
--- a/genprotsym.txr
+++ b/genprotsym.txr
@@ -1,6 +1,24 @@
-@(next (open-files (glob "*.c")))
-@(collect :vars (sym))
-val @(coll)@{sym /[A-Za-z0-9_]+_[sk]/}@/[,;]/@(end)
+@(bind prepro-sym @(hash :equal-based))
+@(bind file-of @(hash :equal-based))
+@(next "Makefile")
+@(repeat)
+@  (cases)
+OBJS-$(have_@sym) += @file.o
+@    (bind ppsym @(upcase-str `HAVE_@sym`))
+@  (or)
+OBJS-$(@sym) += @file.o
+@    (bind ppsym @(upcase-str `CONFIG_@sym`))
+@  (end)
+@  (do (set [prepro-sym `@file.c`] ppsym))
+@(end)
+@(next :list (glob "*.c"))
+@(collect)
+@file
+@  (next file)
+@  (collect :vars ((sym nil)))
+val @(coll)@{sym /[A-Za-z0-9_]+_[sk]/}@/[,;]/@(do (set [file-of sym] file))@(end)
+@  (end)
+@  (flatten sym)
 @(end)
 @(next "lib.c")
 @(collect)
@@ -9,7 +27,9 @@ val @(coll)@{sym /[A-Za-z0-9_]+_[sk]/}@/[,;]/@(end)
 
 @(end)
 @(flatten sym)
-@(bind gsym @(tuples 5 (sort sym)))
+@(bind pp-groups @[group-by [chain file-of prepro-sym] sym])
+@(bind gsym @[mapcar (opip sort (tuples 5)) (hash-values pp-groups)])
+@(bind gpp @(hash-keys pp-groups))
 @(output "protsym.c")
 /* This file is generated by genprotsym.txr */
 
@@ -19,13 +39,21 @@ val @(coll)@{sym /[A-Za-z0-9_]+_[sk]/}@/[,;]/@(end)
 #include "config.h"
 #include "lib.h"
 
-@  (repeat)
+@  (repeat :vars (gpp))
+@    (if gpp `#if @gpp`)
+@    (repeat)
 extern val @(rep)@gsym, @(last)@gsym;@(end)
+@    (end)
+@    (if gpp "#endif")
 @  (end)
 
 val *protected_sym[] = {
-@  (repeat)
+@  (repeat :vars (gpp))
+@    (if gpp `#if @gpp`)
+@    (repeat)
   @(rep)&@gsym, @(last)&@gsym,@(end)
+@    (end)
+@    (if gpp "#endif")
 @  (end)
   convert(val *, 0)
 };