Merge branch 'macro-partial-expansion'

4 files changed, 76 insertions, 16 deletions

diff --git a/CHANGES.current b/CHANGES.current
index 41dbcf559..cbfe89da9 100644
--- a/CHANGES.current
+++ b/CHANGES.current
@@ -7,6 +7,12 @@ the issue number to the end of the URL: https://github.com/swig/swig/issues/
 Version 4.2.0 (in progress)
 ===========================
 
+2023-04-19: mmomtchev
+            https://sourceforge.net/p/swig/bugs/1163/ #2525 Fix preprocessor
+            expansion when a macro expands to the name of another macro which
+            takes parameters from the input following the original macro
+            expansion.
+
 2023-04-19: wildmaples
 	    [Ruby] #2527 Fix "undefining the allocator of T_DATA" warning seen
 	    with Ruby 3.2.
diff --git a/Examples/test-suite/preproc_defined.i b/Examples/test-suite/preproc_defined.i
index 5ebf0a099..401666806 100644
--- a/Examples/test-suite/preproc_defined.i
+++ b/Examples/test-suite/preproc_defined.i
@@ -123,3 +123,31 @@ void another_macro_checking(void) {
 #if 0
 # wobble wobble
 #endif
+
+/* Regression test for https://sourceforge.net/p/swig/bugs/1163/
+ * ONE(1)(2) should expand to `2` but SWIG was expanding it to `TWO(2)`
+ * which results in the generated C wrapper failing to compile.
+ */
+#define ONE(X) TWO
+#define TWO(X) X
+%constant int a = ONE(1)(2);
+#define XXX TWO
+%constant int b = XXX(42);
+#undef ONE
+#undef TWO
+
+/*
+ * The behaviour of Self-Referential Macros is defined
+ * https://gcc.gnu.org/onlinedocs/gcc-4.8.5/cpp/Self-Referential-Macros.html
+ */
+%inline %{
+int y = 0;
+%}
+
+#define x (4 + y)
+#define y (2 * x)
+
+%constant int z = y;
+
+#undef y
+#undef x
diff --git a/Examples/test-suite/python/preproc_defined_runme.py b/Examples/test-suite/python/preproc_defined_runme.py
index af46816be..37441db52 100644
--- a/Examples/test-suite/python/preproc_defined_runme.py
+++ b/Examples/test-suite/python/preproc_defined_runme.py
@@ -9,3 +9,12 @@ d.defined = 10
 preproc_defined.thing(10)
 preproc_defined.stuff(10)
 preproc_defined.bumpf(10)
+
+if preproc_defined.a != 2:
+    raise RuntimeError
+
+if preproc_defined.b != 42:
+    raise RuntimeError
+
+if preproc_defined.z != 8:
+    raise RuntimeError
diff --git a/Source/Preprocessor/cpp.c b/Source/Preprocessor/cpp.c
index 10faa17d5..55058fc13 100644
--- a/Source/Preprocessor/cpp.c
+++ b/Source/Preprocessor/cpp.c
@@ -42,7 +42,7 @@ static const String * macro_start_file = 0;
 /* Test a character to see if it valid in an identifier (after the first letter) */
 #define isidchar(c) ((isalnum(c)) || (c == '_') || (c == '$'))
 
-static DOH *Preprocessor_replace(DOH *);
+static DOH *Preprocessor_replace(DOH *, DOH *);
 
 /* Skip whitespace */
 static void skip_whitespace(String *s, String *out) {
@@ -707,7 +707,7 @@ static String *get_filename(String *str, int *sysfile) {
       Putc(c, fn);
     if (isspace(c))
       Ungetc(c, str);
-    preprocessed_str = Preprocessor_replace(fn);
+    preprocessed_str = Preprocessor_replace(fn, NULL);
     Seek(preprocessed_str, 0, SEEK_SET);
     Delete(fn);
 
@@ -785,7 +785,7 @@ bad:
  * of error occurred.
  * name - name of the macro
  * args - arguments passed to the macro
- * line_file - only used for line/file name when reporting errors
+ * line_file - global context, used for line/file name when reporting errors
  * ----------------------------------------------------------------------------- */
 
 static String *expand_macro(String *name, List *args, String *line_file) {
@@ -903,7 +903,7 @@ static String *expand_macro(String *name, List *args, String *line_file) {
       DOH *arg, *aname;
       String *reparg;
       arg = Getitem(args, i);	/* Get an argument value */
-      reparg = Preprocessor_replace(arg);
+      reparg = Preprocessor_replace(arg, NULL);
       aname = Getitem(margs, i);	/* Get macro argument name */
       if (strstr(Char(ns), "\001")) {
 	/* Try to replace a quoted version of the argument */
@@ -1009,7 +1009,7 @@ static String *expand_macro(String *name, List *args, String *line_file) {
   /* Expand this macro even further */
   Setattr(macro, kpp_expanded, "1");
 
-  e = Preprocessor_replace(ns);
+  e = Preprocessor_replace(ns, line_file);
 
   Delattr(macro, kpp_expanded);
   Delete(ns);
@@ -1047,7 +1047,7 @@ static String *expand_macro(String *name, List *args, String *line_file) {
 }
 
 /* -----------------------------------------------------------------------------
- * DOH *Preprocessor_replace(DOH *s)
+ * DOH *Preprocessor_replace(DOH *s, DOH *line_file)
  *
  * Performs a macro substitution on a string s.  Returns a new string with
  * substitutions applied.   This function works by walking down s and looking
@@ -1057,7 +1057,7 @@ static String *expand_macro(String *name, List *args, String *line_file) {
 
 /* #define SWIG_PUT_BUFF  */
 
-static DOH *Preprocessor_replace(DOH *s) {
+static DOH *Preprocessor_replace(DOH *s, DOH *line_file) {
   DOH *ns, *symbols, *m;
   int c, i, state = 0;
   String *id = NewStringEmpty();
@@ -1280,14 +1280,31 @@ static DOH *Preprocessor_replace(DOH *s) {
       Replaceall(fn, "\\", "\\\\");
       Printf(ns, "\"%s\"", fn);
       Delete(fn);
-    } else if (Getattr(symbols, id)) {
-      DOH *e;
+    } else if ((m = Getattr(symbols, id))) {
       /* Yes.  There is a macro here */
+      /* If it expects arguments, they must come from `line_file` */
+      DOH *args = 0;
+      DOH *e;
+      int macro_additional_lines = 0;
       /* See if the macro expects arguments */
-      e = expand_macro(id, 0, s);
-      if (e)
+      if (Getattr(m, kpp_args) && line_file) {
+        /* Yep.  We need to go find the arguments and do a substitution */
+        int line = Getline(line_file);
+        args = find_args(line_file, 1, id);
+        macro_additional_lines = Getline(line_file) - line;
+        assert(macro_additional_lines >= 0);
+      } else {
+        args = 0;
+      }
+      e = expand_macro(id, args, s);
+      if (e) {
 	Append(ns, e);
+      }
+      while (macro_additional_lines--) {
+	Putc('\n', ns);
+      }
       Delete(e);
+      Delete(args);
     } else {
       Append(ns, id);
     }
@@ -1343,7 +1360,7 @@ static void add_chunk(DOH *ns, DOH *chunk, int allow) {
   DOH *echunk;
   Seek(chunk, 0, SEEK_SET);
   if (allow) {
-    echunk = Preprocessor_replace(chunk);
+    echunk = Preprocessor_replace(chunk, NULL);
     addline(ns, echunk, allow);
     Delete(echunk);
   } else {
@@ -1614,7 +1631,7 @@ String *Preprocessor_parse(String *s) {
 	    copy_location(m, v);
 	    if (Len(v)) {
 	      Swig_error_silent(1);
-	      v1 = Preprocessor_replace(v);
+	      v1 = Preprocessor_replace(v, NULL);
 	      Swig_error_silent(0);
 	      /*              Printf(stdout,"checking '%s'\n", v1); */
 	      if (!checkpp_id(v1)) {
@@ -1696,7 +1713,7 @@ String *Preprocessor_parse(String *s) {
 	  int val;
 	  String *sval;
 	  expand_defined_operator = 1;
-	  sval = Preprocessor_replace(value);
+	  sval = Preprocessor_replace(value, NULL);
 	  start_level = level;
 	  Seek(sval, 0, SEEK_SET);
 	  /*      Printf(stdout,"Evaluating '%s'\n", sval); */
@@ -1732,7 +1749,7 @@ String *Preprocessor_parse(String *s) {
 	    int val;
 	    String *sval;
 	    expand_defined_operator = 1;
-	    sval = Preprocessor_replace(value);
+	    sval = Preprocessor_replace(value, NULL);
 	    Seek(sval, 0, SEEK_SET);
 	    if (Len(sval) > 0) {
 	      val = Preprocessor_expr(sval, &e);
@@ -1823,7 +1840,7 @@ String *Preprocessor_parse(String *s) {
 	  if (*c) {
 	    if (strncmp(c, "nowarn=", 7) == 0) {
 	      String *val = NewString(c + 7);
-	      String *nowarn = Preprocessor_replace(val);
+	      String *nowarn = Preprocessor_replace(val, NULL);
 	      Swig_warnfilter(nowarn, 1);
 	      Delete(nowarn);
 	      Delete(val);