@node ax_c_declare_block
@unnumberedsec ax_c_declare_block

@majorheading Synopsis

@smallexample
AX_C_DECLARE_BLOCK
@end smallexample

@majorheading Description

The macro will compile a test program to see whether the compiler does
allow new variable declarations in the middle of a C statement block,
i.e. after some non-declaration line. New compilers will allow that
which makes the behave a bit more like C++ - the gcc did support it for
quite a time already.

#define DECLARE_BLOCK_NEEDED says they need to be at the beginning of of
a statement block. Additionally two defines DECLARE_BLOCK @{ and
DECLARE_END @} are being set. That makes it possible to do the following
in your source code (which this macro is really made up for):

@smallexample
 #define ___ DECLARE_BLOCK
 #define ____ DECLARE_END
@end smallexample

@smallexample
 int f() @{
  char buffer[1024];
  fgets(buffer, 1024, stdin);
  ___ int i; int ii = strlen(buffer);
  for (i=0; i < ii; i++) @{
     fputc(buffer[i], stdout);
  @}____;
 @}
@end smallexample

@majorheading Source Code

Download the
@uref{http://git.savannah.gnu.org/gitweb/?p=autoconf-archive.git;a=blob_plain;f=m4/ax_c_declare_block.m4,latest
version of @file{ax_c_declare_block.m4}} or browse
@uref{http://git.savannah.gnu.org/gitweb/?p=autoconf-archive.git;a=history;f=m4/ax_c_declare_block.m4,the
macro's revision history}.

@majorheading License

@w{Copyright @copyright{} 2008 Guido U. Draheim @email{guidod@@gmx.de}}

This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 3 of the License, or (at your
option) any later version.

This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
Public License for more details.

You should have received a copy of the GNU General Public License along
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