From 50cdccf3efaa13dd11d1533b73fb34e0429d5cd6 Mon Sep 17 00:00:00 2001
From: seyko <seyko2@gmail.com>
Date: Tue, 3 Mar 2015 14:19:14 +0300
Subject: [PATCH] Added a gcc preprocessor options -P, -P1

tcc -E -P
  do not output a #line directive, a gcc compatible option

tcc -E -P1
  don't follow a gcc preprocessor style and do output a standard
  #line directive. In such case we don't lose a location info when
  we going to compile a resulting file wtith a compiler not
  understanding a gnu style line info.
---
 libtcc.c |  5 +++++
 tcc.c    |  2 ++
 tcc.h    |  5 +++++
 tccpp.c  | 44 ++++++++++++++++++++++++++++++++++----------
 4 files changed, 46 insertions(+), 10 deletions(-)

diff --git a/libtcc.c b/libtcc.c
index c68221e..3581ffb 100644
--- a/libtcc.c
+++ b/libtcc.c
@@ -1647,6 +1647,7 @@ enum {
     TCC_OPTION_I,
     TCC_OPTION_D,
     TCC_OPTION_U,
+    TCC_OPTION_P,
     TCC_OPTION_L,
     TCC_OPTION_B,
     TCC_OPTION_l,
@@ -1695,6 +1696,7 @@ static const TCCOption tcc_options[] = {
     { "I", TCC_OPTION_I, TCC_OPTION_HAS_ARG },
     { "D", TCC_OPTION_D, TCC_OPTION_HAS_ARG },
     { "U", TCC_OPTION_U, TCC_OPTION_HAS_ARG },
+    { "P", TCC_OPTION_P, TCC_OPTION_HAS_ARG | TCC_OPTION_NOSEP },
     { "L", TCC_OPTION_L, TCC_OPTION_HAS_ARG },
     { "B", TCC_OPTION_B, TCC_OPTION_HAS_ARG },
     { "l", TCC_OPTION_l, TCC_OPTION_HAS_ARG | TCC_OPTION_NOSEP },
@@ -1930,6 +1932,9 @@ PUB_FUNC int tcc_parse_args(TCCState *s, int argc, char **argv)
                 tcc_warning("-E: some compiler action already specified (%d)", s->output_type);
             s->output_type = TCC_OUTPUT_PREPROCESS;
             break;
+        case TCC_OPTION_P:
+            s->Pflag = atoi(optarg) + 1;
+            break;
         case TCC_OPTION_MD:
             s->gen_deps = 1;
             break;
diff --git a/tcc.c b/tcc.c
index 52afca7..7b19114 100644
--- a/tcc.c
+++ b/tcc.c
@@ -45,6 +45,8 @@ static void help(void)
            "  -Idir       add include path 'dir'\n"
            "  -Dsym[=val] define 'sym' with value 'val'\n"
            "  -Usym       undefine 'sym'\n"
+           "  -P          do not output a #line directive\n"
+           "  -P1         use a #line directive in output instead of the gcc style\n"
            "Linker options:\n"
            "  -Ldir       add library path 'dir'\n"
            "  -llib       link with dynamic or static library 'lib'\n"
diff --git a/tcc.h b/tcc.h
index e77a3fb..f268aed 100644
--- a/tcc.h
+++ b/tcc.h
@@ -656,6 +656,11 @@ struct TCCState {
 
     /* output file for preprocessing (-E) */
     FILE *ppfp;
+    enum {
+	LINE_MACRO_OUTPUT_FORMAT_GCC,
+	LINE_MACRO_OUTPUT_FORMAT_NONE,
+	LINE_MACRO_OUTPUT_FORMAT_STD,
+    }    Pflag; 
 
     /* for -MD/-MF: collected dependencies for this compilation */
     char **target_deps;
diff --git a/tccpp.c b/tccpp.c
index ab70ba2..18f3063 100644
--- a/tccpp.c
+++ b/tccpp.c
@@ -3133,6 +3133,26 @@ ST_FUNC void preprocess_new(void)
     }
 }
 
+static void line_macro_output(BufferedFile *f, const char *s, TCCState *s1)
+{
+    switch (s1->Pflag) {
+	case LINE_MACRO_OUTPUT_FORMAT_STD:
+	    /* "tcc -E -P1" case */
+    	    fprintf(s1->ppfp, "# line %d \"%s\"\n", f->line_num, f->filename);
+    	    break;
+
+	case LINE_MACRO_OUTPUT_FORMAT_NONE:
+	    /* "tcc -E -P" case: don't output a line directive */
+	    break;
+
+	case LINE_MACRO_OUTPUT_FORMAT_GCC:
+	default:
+	    /* "tcc -E" case: a gcc standard by default */
+	    fprintf(s1->ppfp, "# %d \"%s\"%s\n", f->line_num, f->filename, s);
+	    break;
+    }
+}
+
 /* Preprocess the current file */
 ST_FUNC int tcc_preprocess(TCCState *s1)
 {
@@ -3158,6 +3178,8 @@ ST_FUNC int tcc_preprocess(TCCState *s1)
         if (tok == TOK_EOF) {
             break;
         } else if (file != file_ref) {
+    	    if (file_ref)
+		line_macro_output(file_ref, "", s1);
             goto print_line;
         } else if (tok == TOK_LINEFEED) {
             if (!token_seen)
@@ -3166,18 +3188,20 @@ ST_FUNC int tcc_preprocess(TCCState *s1)
             token_seen = 0;
         } else if (!token_seen) {
             d = file->line_num - file->line_ref;
-            if (file != file_ref || d < 0 || d >= 8) {
+            if (file != file_ref || d >= 8) {
 print_line:
-                iptr_new = s1->include_stack_ptr;
-                s = iptr_new > iptr ? " 1"
-                  : iptr_new < iptr ? " 2"
-                  : iptr_new > s1->include_stack ? " 3"
-                  : ""
-                  ;
-                iptr = iptr_new;
-                fprintf(s1->ppfp, "# %d \"%s\"%s\n", file->line_num, file->filename, s);
+    		s = "";
+		if (tcc_state->Pflag == LINE_MACRO_OUTPUT_FORMAT_GCC) {
+            	    iptr_new = s1->include_stack_ptr;
+            	    s = iptr_new > iptr ? " 1"
+                    : iptr_new < iptr ? " 2"
+                    : iptr_new > s1->include_stack ? " 3"
+                    : ""
+                    ;
+                }
+        	line_macro_output(file, s, s1);
             } else {
-                while (d)
+                while (d > 0)
                     fputs("\n", s1->ppfp), --d;
             }
             file->line_ref = (file_ref = file)->line_num;