warnings: more improvements to warnings generation

Try to better sort out the necessary dependencies for warning
generation.

Fix regex for cleaning up nasmdoc markup: nasmdoc markup does not
nest, although it may include \} sequences.

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

Makefile.in

@@ -79,6 +79,12 @@ ifeq ($(TRACE),1)
 	CFLAGS += -DNASM_TRACE
 endif
 
+# Don't delete intermediate files
+.SECONDARY:
+
+# Delete files on error
+.DELETE_ON_ERROR:
+
 .SUFFIXES:
 .SUFFIXES: $(X) .$(O) .$(A) .xml .1 .c .i .s .txt .time
 
@@ -191,7 +197,7 @@ ndisasm$(X): $(NDISASM) $(MANIFEST) $(NASMLIB)
 
 # These are specific to certain Makefile syntaxes...
 WARNTIMES = $(WARNFILES:=.time)
-WARNSRCS  = $(LIBOBJ_NW:.$(O)=.c)
+WARNSRCS  = $(LIBOBJ_NW:.$(O)=.c) asm/nasm.c
 
 #-- Begin Generated File Rules --#
 
@@ -286,11 +292,12 @@ x86/regs.h: x86/regs.dat x86/regs.pl
 # reasonable, but doesn't update the time stamp if the files aren't
 # changed, to avoid rebuilding everything every time. Track the actual
 # dependency by the empty file asm/warnings.time.
+.PHONY: warnings
 warnings:
-	$(RM_F) $(WARNFILES) $(WARNTIMES)
+	$(RM_F) $(WARNFILES) $(WARNTIMES) asm/warnings.time
 	$(MAKE) asm/warnings.time
 
-asm/warnings.time: $(WARNSRCS)
+asm/warnings.time: $(WARNSRCS) asm/warnings.pl
 	$(EMPTY) asm/warnings.time
 	$(MAKE) $(WARNTIMES)
 

asm/warnings.pl

@@ -18,10 +18,11 @@ sub quote_for_c(@) {
     return $s;
 }
 
+# Remove a subset of nasmdoc markup
 sub remove_markup(@) {
     my $s = join('', @_);
 
-    $s =~ s/\\[\w+](\{((?:(?>[^{}]+)|(?1))*)\})?/$2/g;
+    $s =~ s/\\[\w+](?:\{((?:[^\}]|\\\})*)\})/$1/g;
     $s =~ s/\\(\W)/$1/g;
     return $s;
 }

doc/Makefile.in

@@ -43,6 +43,12 @@ SRCS		= nasmdoc.src inslist.src changes.src warnings.src version.src
 OUT		= html nasmdoc.txt nasmdoc.pdf $(XZFILES)
 XZOUT           = nasmdoc.pdf.xz
 
+# Don't delete intermediate files
+.SECONDARY:
+
+# Delete files on error
+.DELETE_ON_ERROR:
+
 .SUFFIXES:
 .SUFFIXES: .pfa .ph