diff options
| -rw-r--r-- | handy.h | 7 | ||||
| -rw-r--r-- | perl.c | 4 | ||||
| -rw-r--r-- | perl.h | 7 | ||||
| -rw-r--r-- | pod/perlhacktips.pod | 12 |
4 files changed, 25 insertions, 5 deletions
@@ -69,7 +69,7 @@ Null SV pointer. (No longer available when C<PERL_CORE> is defined.) #define MUTABLE_IO(p) ((IO *)MUTABLE_PTR(p)) #define MUTABLE_SV(p) ((SV *)MUTABLE_PTR(p)) -#ifdef I_STDBOOL +#if defined(I_STDBOOL) && !defined(PERL_BOOL_AS_CHAR) # include <stdbool.h> # ifndef HAS_BOOL # define HAS_BOOL 1 @@ -85,9 +85,11 @@ Null SV pointer. (No longer available when C<PERL_CORE> is defined.) Andy Dougherty February 2000 */ #ifdef __GNUG__ /* GNU g++ has bool built-in */ +# ifndef PERL_BOOL_AS_CHAR # ifndef HAS_BOOL # define HAS_BOOL 1 # endif +# endif #endif /* The NeXT dynamic loader headers will not build with the bool macro @@ -104,6 +106,9 @@ Null SV pointer. (No longer available when C<PERL_CORE> is defined.) #endif /* NeXT || __NeXT__ */ #ifndef HAS_BOOL +# ifdef bool +# undef bool +# endif # define bool char # define HAS_BOOL 1 #endif @@ -42,10 +42,6 @@ # include <sys/sysctl.h> #endif -#ifdef USE_NSGETEXECUTABLEPATH -# include <mach-o/dyld.h> -#endif - #ifdef DEBUG_LEAKING_SCALARS_FORK_DUMP # ifdef I_SYSUIO # include <sys/uio.h> @@ -2298,6 +2298,13 @@ typedef SV PADNAME; # define PERL_SAWAMPERSAND #endif +/* Include mach-o/dyld.h here for perl.c’s sake, since it may #define bool, + and handy.h needs to be able to re#define it under + -Accflags=-DPERL_BOOL_AS_CHAR. */ +#if defined(USE_NSGETEXECUTABLEPATH) && defined(PERL_IN_PERL_C) +# include <mach-o/dyld.h> +#endif + #include "handy.h" #if defined(USE_LARGE_FILES) && !defined(NO_64_BIT_RAWIO) diff --git a/pod/perlhacktips.pod b/pod/perlhacktips.pod index 7851db939a..32739ff690 100644 --- a/pod/perlhacktips.pod +++ b/pod/perlhacktips.pod @@ -1329,6 +1329,18 @@ op slabs belonging to C<BEGIN> blocks. However, as an 80% solution it is still effective, as it has caught bugs in the past. +=head2 When is a bool not a bool? + +On pre-C99 compilers, C<bool> is defined as equivalent to C<char>. +Consequently assignment of any larger type to a C<bool> is unsafe and may +be truncated. The C<cBOOL> macro exists to cast it correctly. + +On those platforms and compilers where C<bool> really is a boolean (C++, +C99), it is easy to forget the cast. You can force C<bool> to be a C<char> +by compiling with C<-Accflags=-DPERL_BOOL_AS_CHAR>. You may also wish to +add C<-Accflags=-Werror=conversion> or your compiler's equivalent to make +it impossible to ignore the unsafe truncations. + =head2 The .i Targets You can expand the macros in a F<foo.c> file by saying |