On Mon, Jun 4, 2012 at 2:40 PM, Steven Bosscher <stevenb....@gmail.com> wrote:
> asm_out_file for PCH:
> c-family/c-pch.c:#include "output.h" /* for asm_out_file */
> c-family/c-pch.c: fprintf (asm_out_file, "%s ", ASM_COMMENT_START);
> c-family/c-pch.c: c_common_print_pch_checksum (asm_out_file);
> c-family/c-pch.c: fputc ('\n', asm_out_file);
> c-family/c-pch.c: asm_file_startpos = ftell (asm_out_file);
> c-family/c-pch.c: asm_file_end = ftell (asm_out_file);
> c-family/c-pch.c: if (fseek (asm_out_file, asm_file_startpos, SEEK_SET) != 0)
> c-family/c-pch.c: if (fread (buf, size, 1, asm_out_file) != 1)
> c-family/c-pch.c: if (fseek (asm_out_file, 0, SEEK_END) != 0)
> c-family/c-pch.c: || fwrite (buf, size, 1, asm_out_file) != 1)
> c-family/c-pch.c: asm_out_file. */
>
> I do not understand this at all. In what way does PCH have anything to
> do with writing out to asm_out_file?!
FWIW, the following patchlet passes bootstrap and testing of pch.exp:
Index: c-pch.c
===================================================================
--- c-pch.c (revision 188177)
+++ c-pch.c (working copy)
@@ -188,6 +188,7 @@ c_common_write_pch (void)
asm_file_end = ftell (asm_out_file);
h.asm_size = asm_file_end - asm_file_startpos;
+ gcc_assert (! h.asm_size);
if (fwrite (&h, sizeof (h), 1, pch_outfile) != 1)
fatal_error ("can%'t write %s: %m", pch_file);
Could it be that this is just a relic of the pre-unit-at-a-time days?
Ciao!
Steven
