2010/7/23 Eric Blake <eblake@redhat.com>:
This would have detected the bug in commit 38ad33931 (Aug 09), which we missed until commit f828ca35 (Jul 10); over 11 months later.
However, on Fedora 13, it also triggers LOTS of warnings from the libcurl-devel header for one file:
esx/esx_vi.c: In function 'esxVI_CURL_Perform': esx/esx_vi.c:232: error: logical '&&' with non-zero constant will always evaluate as true [-Wlogical-op] esx/esx_vi.c:232: error: logical '&&' with non-zero constant will always evaluate as true [-Wlogical-op] esx/esx_vi.c:232: error: logical '&&' with non-zero constant will always evaluate as true [-Wlogical-op] ...
I figure the gross hack to disable the warnings in the third-party code, along with the reduction in type-safety in just esx_vi.c, is worth the improved compiler checking throughout the rest of libvirt.
* acinclude.m4 (--enable-compile-warnings=error): Add -Wlogical-op. * src/esx/esx_vi.c (includes): Hack around broken libcurl-devel header, to avoid compilation warning. Suggested by Daniel P. Berrange. ---
In response to https://www.redhat.com/archives/libvir-list/2010-July/msg00497.html and fixing some long lines while I was at it.
acinclude.m4 | 16 +++++++++++++--- src/esx/esx_vi.c | 10 ++++++++++ 2 files changed, 23 insertions(+), 3 deletions(-)
@@ -36,6 +36,16 @@ #include "esx_vi_methods.h" #include "esx_util.h"
+ +/* XXX "esx_vi.h" includes <curl/curl.h>; as of + * libcurl-devel-7.20.1-3.fc13.x86_64, curl ships a version of this + * header that #defines several wrapper macros around underlying + * functions to add type safety for gcc only. However, these macros + * spuriously trip gcc's -Wlogical-op warning. Avoid the warning by + * nuking the wrappers; even if it removes some type-check safety. */ +# undef curl_easy_getinfo +# undef curl_easy_setopt + #define VIR_FROM_THIS VIR_FROM_ESX
No need to hack here. We can define CURL_DISABLE_TYPECHECK to disable those type checks. Also the warnings are not that spuriously. If you look at typecheck-gcc.h you'll see that the condition of the if clauses only depend onto type information. This type information is static at compile- and runtime, so gcc is correct to warn about them being fixed true or false. This also affects the XenAPI driver because it includes curl.h too. Therefore, I suggest the attached variation of your patch. Matthias