preproc: don't handle %+ until the final phase of smacro expansion

Revert to the earlier behavior of not expanding %+ until the final
phase of smacro expansion.  However, the previous code has:

    if (expanded && paste_tokens(&thead, true)) {

... which would inhibit paste_tokens() if expanded was false on the
first iteration.  However, if expand_mmac_params is not expanding %+,
then we cannot bypass this expansion.  Thus use:

    pasted = paste_tokens(&thead, true);
    if (expanded && pasted) {

... instead.

This seems to work with both Syslinux and x264 usage, and therefore
hopefully should be compatible with earlier versions of NASM.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 8 insertions, 4 deletions

diff --git a/preproc.c b/preproc.c
index 9a1ca306..8470dff4 100644
--- a/preproc.c
+++ b/preproc.c
@@ -3611,7 +3611,7 @@ static Token *expand_mmac_params(Token * tline)
     *tail = NULL;
 
     if (changed)
-	paste_tokens(&thead, true);
+	paste_tokens(&thead, false);
 
     return thead;
 }
@@ -3638,7 +3638,7 @@ static Token *expand_smacro(Token * tline)
     Context *ctx;
     const char *mname;
     int deadman = DEADMAN_LIMIT;
-    bool expanded;
+    bool expanded, pasted;
 
     /*
      * Trick: we should avoid changing the start token pointer since it can
@@ -3928,8 +3928,12 @@ again:
      * Also we look for %+ tokens and concatenate the tokens before and after
      * them (without white spaces in between).
      */
-    if (expanded && paste_tokens(&thead, true)) {
-	/* If we concatenated something, re-scan the line for macros */
+    pasted = paste_tokens(&thead, true);
+    if (expanded && pasted) {
+	/*
+	 * If we concatenated something, *and* we had previously expanded
+	 * an actual macro, scan the lines again for macros...
+	 */
         tline = thead;
         goto again;
     }