Generate function-local error indicator variables whenever "error_goto()" is used.

This was previously broken by the introduction of the "__PYX_ERR()" macro.

Cython/Compiler/Code.py

@@ -2344,24 +2344,18 @@ class CCodeWriter(object):
         self.funcstate.should_declare_error_indicator = True
         if used:
             self.funcstate.uses_error_indicator = True
-        if self.code_config.c_line_in_traceback:
-            cinfo = " %s = %s;" % (Naming.clineno_cname, Naming.line_c_macro)
-        else:
-            cinfo = ""
-
-        return "%s = %s[%s]; %s = %s;%s" % (
-            Naming.filename_cname,
-            Naming.filetable_cname,
+        return "__PYX_MARK_ERR_POS(%s, %s)" % (
             self.lookup_filename(pos[0]),
-            Naming.lineno_cname,
-            pos[1],
-            cinfo)
+            pos[1])
 
-    def error_goto(self, pos):
+    def error_goto(self, pos, used=True):
         lbl = self.funcstate.error_label
         self.funcstate.use_label(lbl)
         if pos is None:
             return 'goto %s;' % lbl
+        self.funcstate.should_declare_error_indicator = True
+        if used:
+            self.funcstate.uses_error_indicator = True
         return "__PYX_ERR(%s, %s, %s)" % (
             self.lookup_filename(pos[0]),
             pos[1],

Cython/Compiler/ModuleNode.py

@@ -658,16 +658,19 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
         self._put_setup_code(code, "PythonCompatibility")
         self._put_setup_code(code, "MathInitCode")
 
+        # Using "(void)cname" to prevent "unused" warnings.
         if options.c_line_in_traceback:
-            cinfo = "%s = %s; " % (Naming.clineno_cname, Naming.line_c_macro)
+            cinfo = "%s = %s; (void)%s; " % (Naming.clineno_cname, Naming.line_c_macro, Naming.clineno_cname)
         else:
             cinfo = ""
-        code.put("""
-#define __PYX_ERR(f_index, lineno, Ln_error) \\
-{ \\
-  %s = %s[f_index]; %s = lineno; %sgoto Ln_error; \\
-}
-""" % (Naming.filename_cname, Naming.filetable_cname, Naming.lineno_cname, cinfo))
+        code.putln("#define __PYX_MARK_ERR_POS(f_index, lineno) \\")
+        code.putln("    { %s = %s[f_index]; (void)%s; %s = lineno; (void)%s; %s}" % (
+            Naming.filename_cname, Naming.filetable_cname, Naming.filename_cname,
+            Naming.lineno_cname, Naming.lineno_cname,
+            cinfo
+        ))
+        code.putln("#define __PYX_ERR(f_index, lineno, Ln_error) \\")
+        code.putln("    { __PYX_MARK_ERR_POS(f_index, lineno) goto Ln_error; }")
 
         code.putln("")
         self.generate_extern_c_macro_definition(code)