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| author | Mark H Weaver <mhw@netris.org> | 2013-07-18 14:10:43 -0400 |
|---|---|---|
| committer | Mark H Weaver <mhw@netris.org> | 2013-07-18 14:23:32 -0400 |
| commit | 824b9ad8b792ab42c5cc614d66462dfaab489075 (patch) | |
| tree | c0868cc8a2c1ce39c6923a5937bcac8a00b8d75f /libguile/tags.h | |
| parent | fe51c7b3e0a1e93be3bb81dd2d4b18936fe2df3a (diff) | |
| download | guile-824b9ad8b792ab42c5cc614d66462dfaab489075.tar.gz | |
Modify SCM_UNPACK type check to avoid warnings in clang.
* libguile/tags.h (SCM_UNPACK): Change (*(SCM*)0=(x)) to
(*(volatile SCM *)0=(x)), to avoid null-dereference warnings
from clang. Reported by Shane Celis <shane.celis@gmail.com>.
Diffstat (limited to 'libguile/tags.h')
| -rw-r--r-- | libguile/tags.h | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/libguile/tags.h b/libguile/tags.h index a3032bfa9..c41543ffd 100644 --- a/libguile/tags.h +++ b/libguile/tags.h @@ -87,14 +87,15 @@ typedef union SCM { struct { scm_t_bits n; } n; } SCM; The 0?: constructions makes sure that the code is never executed, and that there is no performance hit. However, the alternative is compiled, and does generate a warning when used with the wrong - pointer type. + pointer type. We use a volatile pointer type to avoid warnings + from clang. The Tru64 and ia64-hp-hpux11.23 compilers fail on `case (0?0=0:x)' statements, so for them type-checking is disabled. */ #if defined __DECC || defined __HP_cc # define SCM_UNPACK(x) ((scm_t_bits) (x)) #else -# define SCM_UNPACK(x) ((scm_t_bits) (0? (*(SCM*)0=(x)): x)) +# define SCM_UNPACK(x) ((scm_t_bits) (0? (*(volatile SCM *)0=(x)): x)) #endif /* |