[Java PATCH] Generate declarations in jvgenmain.c

[Java PATCH] Generate declarations in jvgenmain.c

[Marek Polacek]

[CCing java-patches now]

Java testsuite breaks with -std=gnu11 as a default and/or with 
-Wimplicit-function-declaration on, since the jvgenmain.c program
that generates a C file containing 'main' function which calls either
'JvRunMainName' or 'JvRunMain' does not generate forward declarations
for these functions.  The following patch generates such a declaration
depending on whether -findirect-dispatch is given.

Bootstrapped/regtested on x86_64-linux, ok for trunk?

2014-10-07  Marek Polacek  <polacek@redhat.com>

	* jvgenmain.c (main): Provide declaration for JvRunMain{,Name}.

diff --git gcc/java/jvgenmain.c gcc/java/jvgenmain.c
index 5b14258..82e468d 100644
--- gcc/java/jvgenmain.c
+++ gcc/java/jvgenmain.c
@@ -127,6 +127,10 @@ main (int argc, char **argv)
   /* At this point every element of ARGV from 1 to LAST_ARG is a `-D'
      option.  Process them appropriately.  */
   fprintf (stream, "extern const char **_Jv_Compiler_Properties;\n");
+  if (indirect)
+    fprintf (stream, "extern void JvRunMainName ();\n");
+  else
+    fprintf (stream, "extern void JvRunMain ();\n");
   fprintf (stream, "static const char *props[] =\n{\n");
   for (i = 1; i < last_arg; ++i)
     {

	Marek

Re: [Java PATCH] Generate declarations in jvgenmain.c

[Andrew Haley]

On 10/07/2014 09:31 AM, Marek Polacek wrote:
> Bootstrapped/regtested on x86_64-linux, ok for trunk?

OK, thanks.

Andrew.

Re: [Java PATCH] Generate declarations in jvgenmain.c

[Tom Tromey]

>>>>> "Marek" == Marek Polacek <polacek@redhat.com> writes:

Marek> [CCing java-patches now]
Marek> Java testsuite breaks with -std=gnu11 as a default and/or with 
Marek> -Wimplicit-function-declaration on

I don't recall how one gets warnings when compiling this generated code,
but if it is generally possible then I think this:

Marek> +  if (indirect)
Marek> +    fprintf (stream, "extern void JvRunMainName ();\n");
Marek> +  else
Marek> +    fprintf (stream, "extern void JvRunMain ();\n");

... will fail with -Wstrict-prototypes, since in C those should
read "(void)" rather than "()".

If it's not possible then no big deal.

Tom

Re: [Java PATCH] Generate declarations in jvgenmain.c

[Marek Polacek]

On Tue, Oct 07, 2014 at 10:03:26AM -0600, Tom Tromey wrote:
> >>>>> "Marek" == Marek Polacek <polacek@redhat.com> writes:
> 
> Marek> [CCing java-patches now]
> Marek> Java testsuite breaks with -std=gnu11 as a default and/or with 
> Marek> -Wimplicit-function-declaration on
> 
> I don't recall how one gets warnings when compiling this generated code,
> but if it is generally possible then I think this:

I'm not sure I understand, but this piece of code gets compiled when
running the libjava testsuite.  And when the warning triggers, we get
many fails.
 
> Marek> +  if (indirect)
> Marek> +    fprintf (stream, "extern void JvRunMainName ();\n");
> Marek> +  else
> Marek> +    fprintf (stream, "extern void JvRunMain ();\n");
> 
> ... will fail with -Wstrict-prototypes, since in C those should
> read "(void)" rather than "()".
> 
> If it's not possible then no big deal.

I saw declarations of JvRunMain{,Name} with no parameters and with
some parameters.  So I decided to make it prototype-less function
declaration for now.  I think we don't have to worry about
-Wstrict-prototypes for now.

	Marek

Re: [Java PATCH] Generate declarations in jvgenmain.c

[Tom Tromey]

Marek> I saw declarations of JvRunMain{,Name} with no parameters and with
Marek> some parameters.

Oh yeah, duh.

Marek>  So I decided to make it prototype-less function
Marek> declaration for now.  I think we don't have to worry about
Marek> -Wstrict-prototypes for now.

Thanks for looking.

Tom