Bug#373647: bug due to broken gcc-4.1 amd64 code generation

[Vincent Fourmond]

Package: fftw
Followup-For: Bug #373647

  Hello !

  I found the problem that causes the FTBS: a buggy code generation in gcc 
causes a loop to make 
18446744071562067968 iterations instead of 2147483648. A workaround is provided 
as a patch. A bug 
report has been submitted to gcc (#376213).

  Regards,

        Vincent Fourmond


-- System Information:
Debian Release: testing/unstable
  APT prefers unstable
  APT policy: (500, 'unstable')
Architecture: amd64 (x86_64)
Shell:  /bin/sh linked to /bin/bash
Kernel: Linux 2.6.16
Locale: LANG=fr_FR, LC_CTYPE=fr_FR (charmap=ISO-8859-1) (ignored: LC_ALL set to 
en_GB)

--- fftw-2.1.3/tests/test_main.c	1999-10-26 23:45:06.000000000 +0200
+++ fftw-2.1.3.new/tests/test_main.c	2006-07-01 00:53:31.000000000 +0200
@@ -559,7 +559,8 @@
      start = fftw_get_time();
 
      for (i = 0; i < 32; i++) {
-	  iters = 1 << i;
+          if(i) iters <<= 1; 
+	  else iters = 1; /* work around buggy gcc-4.1 amd64 code generation */
 	  tmin = 1.0E10;
 	  tmax = -1.0E10;