Fix #1940536, overactive preprocessor which was expanding defined(...) outside of #if and #elif preprocessor directives.

git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk@12441 626c5289-ae23-0410-ae9c-e8d60b6d4f22

CHANGES.current

@@ -5,6 +5,9 @@ See the RELEASENOTES file for a summary of changes in each release.
 Version 2.0.2 (in progress)
 ===========================
 
+2011-02-07: wsfulton
+            Fix #1940536, overactive preprocessor which was expanding defined(...) outside of #if and #elif
+            preprocessor directives.
 
 2011-02-05: wsfulton
             [MzScheme] SF #2942899 Add user supplied documentation to help getting started with MzScheme.

Examples/test-suite/common.mk

@@ -493,6 +493,7 @@ C_TEST_CASES += \
 	overload_extendc \
 	preproc \
 	preproc_constants_c \
+	preproc_defined \
 	preproc_line_file \
 	ret_by_value \
 	simple_array \

Examples/test-suite/preproc_defined.i

@@ -0,0 +1,36 @@
+%module preproc_defined
+
+// Check 'defined' passes through the preprocessor without being processed like '#if defined(ABC)' would be (SF bug #1940536)
+
+%define DEFINED_MACRO
+%{
+  int defined(int b) { 
+    return b > 10;
+  }
+  int vvv = -1;
+  void fn(int val) {
+    if (defined(val))
+      vvv = 1;
+    else
+      vvv = 0; 
+  }
+%}
+%enddef
+
+DEFINED_MACRO
+
+%{
+int checking(void) {
+  fn(11);
+  int okay = (vvv == 1);
+  fn(9);
+  okay = okay && (vvv == 0);
+  return okay; /* should be 1 */
+}
+%}
+
+%inline %{
+int call_checking(void) {
+  return checking();
+}
+%}

Examples/test-suite/python/preproc_defined_runme.py

@@ -0,0 +1,4 @@
+import preproc_defined
+
+if preproc_defined.call_checking() != 1:
+  raise RuntimeError

Source/Preprocessor/cpp.c

@@ -33,6 +33,7 @@ static Hash *included_files = 0;
 static List *dependencies = 0;
 static Scanner *id_scan = 0;
 static int error_as_warning = 0;	/* Understand the cpp #error directive as a special #warning */
+static int defined_operator_accepted = 0;
 static int macro_level = 0;
 static int macro_start_line = 0;
 static const String * macro_start_file = 0;
@@ -1013,8 +1014,8 @@ static DOH *Preprocessor_replace(DOH *s) {
       } else {
 	/* We found the end of a valid identifier */
 	Ungetc(c, s);
-	/* See if this is the special "defined" macro */
-	if (Equal(kpp_defined, id)) {
+	/* See if this is the special "defined" operator */
+	if (Equal(kpp_defined, id) && defined_operator_accepted) {
 	  int lenargs = 0;
 	  DOH *args = 0;
 	  /* See whether or not a parenthesis has been used */
@@ -1042,7 +1043,7 @@ static DOH *Preprocessor_replace(DOH *s) {
 	  }
 	  lenargs = Len(args);
 	  if ((!args) || (!lenargs)) {
-	    /* This is not a defined() macro. */
+	    /* This is not a defined() operator. */
 	    Append(ns, id);
 	    state = 0;
 	    break;
@@ -1554,7 +1555,9 @@ String *Preprocessor_parse(String *s) {
 	level++;
 	if (allow) {
 	  int val;
-	  String *sval = Preprocessor_replace(value);
+	  String *sval;
+	  defined_operator_accepted = 1;
+	  sval = Preprocessor_replace(value);
 	  start_level = level;
 	  Seek(sval, 0, SEEK_SET);
 	  /*      Printf(stdout,"Evaluating '%s'\n", sval); */
@@ -1570,6 +1573,7 @@ String *Preprocessor_parse(String *s) {
 	    if (val == 0)
 	      allow = 0;
 	  }
+	  defined_operator_accepted = 0;
 	  mask = 1;
 	}
       } else if (Equal(id, kpp_elif)) {
@@ -1577,6 +1581,7 @@ String *Preprocessor_parse(String *s) {
 	  Swig_error(Getfile(s), Getline(id), "Misplaced #elif.\n");
 	} else {
 	  cond_lines[level - 1] = Getline(id);
+	  defined_operator_accepted = 1;
 	  if (allow) {
 	    allow = 0;
 	    mask = 0;
@@ -1599,6 +1604,7 @@ String *Preprocessor_parse(String *s) {
 		allow = 0;
 	    }
 	  }
+	  defined_operator_accepted = 0;
 	}
       } else if (Equal(id, kpp_warning)) {
 	if (allow) {