Fixed processing '\\' followed with a newline and line number output (-E) with it.

src/cc65/input.c

@@ -578,15 +578,16 @@ int NextLine (void)
                 SB_Drop (Line, 1);
             }
 
-            /* If we don't have a line continuation character at the end,
-            ** we're done with this line. Otherwise replace the character
-            ** by a newline and continue reading.
+            /* If we don't have a line continuation character at the end, we
+            ** are done with this line. Otherwise just skip the character and
+            ** continue reading.
             */
-            if (SB_LookAtLast (Line) == '\\') {
-                Line->Buf[Line->Len-1] = '\n';
-            } else {
+            if (SB_LookAtLast (Line) != '\\') {
                 Input->MissingNL = 0;
                 break;
+            } else {
+                SB_Drop (Line, 1);
+                ContinueLine ();
             }
 
         } else if (C != '\0') {         /* Ignore embedded NULs */

src/cc65/preproc.c

@@ -114,7 +114,8 @@ static StrBuf* MLine;   /* Buffer for macro expansion in #pragma */
 static StrBuf* OLine;   /* Buffer for #pragma output */
 
 /* Newlines to be added to preprocessed text */
-static int PendingNewLines;
+static unsigned PendingNewLines;
+static unsigned ContinuedLines;
 static int FileChanged;
 
 /* Structure used when expanding macros */
@@ -824,18 +825,24 @@ static void CheckForBadIdent (const char* Ident, int Std, const Macro* M)
 static void AddPreLine (StrBuf* Str)
 /* Add newlines to the string buffer */
 {
+    /* No need to prettify the non-exist output */
     if (!PreprocessOnly) {
         PendingNewLines = 0;
+        ContinuedLines = 0;
         return;
     }
 
+    /* We'll adjust the line number later if necessary */
+    PendingNewLines += ContinuedLines;
+
     if (FileChanged || PendingNewLines > 6) {
         /* Output #line directives as source info */
         StrBuf Comment = AUTO_STRBUF_INITIALIZER;
         if (SB_NotEmpty (Str) && SB_LookAtLast (Str) != '\n') {
             SB_AppendChar (Str, '\n');
         }
-        SB_Printf (&Comment, "#line %u \"%s\"\n", GetCurrentLine (), GetCurrentFile ());
+        SB_Printf (&Comment, "#line %u \"%s\"\n",
+                   GetCurrentLine () - ContinuedLines, GetCurrentFile ());
         SB_Append (Str, &Comment);
     } else {
         /* Output new lines */
@@ -846,6 +853,7 @@ static void AddPreLine (StrBuf* Str)
     }
     FileChanged = 0;
     PendingNewLines = 0;
+    ContinuedLines = 0;
 }
 
 
@@ -1528,14 +1536,14 @@ static unsigned ReadMacroArgs (unsigned NameIdx, MacroExp* E, const Macro* M, in
     /* Read the actual macro arguments */
     while (1) {
         /* Squeeze runs of blanks within an arg */
-        int OldPendingNewLines = PendingNewLines;
+        unsigned OldPendingNewLines = PendingNewLines;
         int Skipped = SkipWhitespace (MultiLine);
 
         /* Directives can only be found in an argument list that spans
         ** multiple lines.
         */
         if (MultiLine && OldPendingNewLines < PendingNewLines && CurC == '#') {
-            int Newlines = 0;
+            unsigned Newlines = 0;
 
             while (OldPendingNewLines < PendingNewLines && CurC == '#') {
                 Newlines += PendingNewLines - OldPendingNewLines;
@@ -3362,6 +3370,14 @@ void SetPPIfStack (PPIfStack* Stack)
 
 
 
+void ContinueLine (void)
+/* Continue the current line ended with a '\\' */
+{
+    ++ContinuedLines;
+}
+
+
+
 void PreprocessBegin (void)
 /* Initialize preprocessor with current file */
 {

src/cc65/preproc.h

@@ -68,6 +68,9 @@ void Preprocess (void);
 void SetPPIfStack (PPIfStack* Stack);
 /* Specify which PP #if stack to use */
 
+void ContinueLine (void);
+/* Continue the current line ended with a '\\' */
+
 void PreprocessBegin (void);
 /* Initialize preprocessor with current file */
 

test/val/bug1891.c

@@ -0,0 +1,19 @@
+/* bug #1891 - backslash/newline sequence in string constants is treated wrong */
+
+#include <stdio.h>
+#include <string.h>
+
+const char* a = "hello \
+world";
+const char* b = \
+"hello world";
+
+int main(void)
+{
+    if (strcmp(a, b) != 0) {
+        printf("a:\n%s\n", a);
+        printf("b:\n%s\n", b);
+        return 1;
+    }
+    return 0;
+}