Potential usage of an uninitialized variable - Rebuild of the Debian archive with clang

"Potential usage of an uninitialized variable" build failure(s) — clang 3.3

int f(int b) {
  int n;
  if (b)
    n = 1;
  return n;
}

In some cases, n can be uninitialized.
gcc -Werror plop.c will accept this code while clang -Werror plop.c will fail.

Package	Version	Supposed error message	Full log	Bug report
altermime	0.3.10-7	mime_alter.c:709:13: error: variable 'newblock' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]	Log	753058
libnss-cache	0.10.2-1	nss_cache.c:155:11: error: variable 'ret' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]	Log	745258
libpfm4	4.3.0-1	self_count.c:157:11: error: variable 'idx' is used uninitialized whenever 'do' loop exits because its condition is false [-Werror,-Wsometimes-uninitialized]	Log
tpm-tools	1.3.8-1	tpm_present.c:189:9: error: variable 'hTpmPolicy' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]	Log	753063
tuxpuck	0.8.2-2.2	ttf2font.c:56:7: error: variable 'ysize' is used uninitialized whenever '\|\|' condition is true [-Werror,-Wsometimes-uninitialized]	Log	753064
u1db	0.1.4-2	u1db_query.c:912:9: error: variable 'statement' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]	Log
x86info	1.30-3	lsmsr.c:168:6: error: variable 'val' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]	Log	753066

7 errors