diff options
| -rwxr-xr-x | configure | 71 | ||||
| -rw-r--r-- | configure.in | 1 | ||||
| -rw-r--r-- | src/include/access/gist.h | 2 | ||||
| -rw-r--r-- | src/include/pg_config.h.in | 9 |
4 files changed, 82 insertions, 1 deletions
diff --git a/configure b/configure index a2c3aab407b..9b8cb48931d 100755 --- a/configure +++ b/configure @@ -14954,6 +14954,77 @@ _ACEOF fi + + { $as_echo "$as_me:$LINENO: checking for flexible array members" >&5 +$as_echo_n "checking for flexible array members... " >&6; } +if test "${ac_cv_c_flexmember+set}" = set; then + $as_echo_n "(cached) " >&6 +else + cat >conftest.$ac_ext <<_ACEOF +/* confdefs.h. */ +_ACEOF +cat confdefs.h >>conftest.$ac_ext +cat >>conftest.$ac_ext <<_ACEOF +/* end confdefs.h. */ +#include <stdlib.h> + #include <stdio.h> + #include <stddef.h> + struct s { int n; double d[]; }; +int +main () +{ +int m = getchar (); + struct s *p = malloc (offsetof (struct s, d) + + m * sizeof (double)); + p->d[0] = 0.0; + return p->d != (double *) NULL; + ; + return 0; +} +_ACEOF +rm -f conftest.$ac_objext +if { (ac_try="$ac_compile" +case "(($ac_try" in + *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;; + *) ac_try_echo=$ac_try;; +esac +eval ac_try_echo="\"\$as_me:$LINENO: $ac_try_echo\"" +$as_echo "$ac_try_echo") >&5 + (eval "$ac_compile") 2>conftest.er1 + ac_status=$? + grep -v '^ *+' conftest.er1 >conftest.err + rm -f conftest.er1 + cat conftest.err >&5 + $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5 + (exit $ac_status); } && { + test -z "$ac_c_werror_flag" || + test ! -s conftest.err + } && test -s conftest.$ac_objext; then + ac_cv_c_flexmember=yes +else + $as_echo "$as_me: failed program was:" >&5 +sed 's/^/| /' conftest.$ac_ext >&5 + + ac_cv_c_flexmember=no +fi + +rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext +fi +{ $as_echo "$as_me:$LINENO: result: $ac_cv_c_flexmember" >&5 +$as_echo "$ac_cv_c_flexmember" >&6; } + if test $ac_cv_c_flexmember = yes; then + +cat >>confdefs.h <<\_ACEOF +#define FLEXIBLE_ARRAY_MEMBER /**/ +_ACEOF + + else + cat >>confdefs.h <<\_ACEOF +#define FLEXIBLE_ARRAY_MEMBER 1 +_ACEOF + + fi + { $as_echo "$as_me:$LINENO: checking for signed types" >&5 $as_echo_n "checking for signed types... " >&6; } if test "${pgac_cv_c_signed+set}" = set; then diff --git a/configure.in b/configure.in index ddc4cc9a167..e873c7b1572 100644 --- a/configure.in +++ b/configure.in @@ -1110,6 +1110,7 @@ AC_C_BIGENDIAN AC_C_CONST PGAC_C_INLINE AC_C_STRINGIZE +AC_C_FLEXIBLE_ARRAY_MEMBER PGAC_C_SIGNED AC_C_VOLATILE PGAC_C_FUNCNAME_SUPPORT diff --git a/src/include/access/gist.h b/src/include/access/gist.h index df9f39c7b89..5ce7325ff9b 100644 --- a/src/include/access/gist.h +++ b/src/include/access/gist.h @@ -144,7 +144,7 @@ typedef struct GISTENTRY typedef struct { int32 n; /* number of elements */ - GISTENTRY vector[1]; /* variable-length array */ + GISTENTRY vector[FLEXIBLE_ARRAY_MEMBER]; } GistEntryVector; #define GEVHDRSZ (offsetof(GistEntryVector, vector)) diff --git a/src/include/pg_config.h.in b/src/include/pg_config.h.in index 5d38f25d263..19f38cc0fd0 100644 --- a/src/include/pg_config.h.in +++ b/src/include/pg_config.h.in @@ -61,6 +61,15 @@ (--enable-thread-safety) */ #undef ENABLE_THREAD_SAFETY +/* Define to nothing if C supports flexible array members, and to 1 if it does + not. That way, with a declaration like `struct s { int n; double + d[FLEXIBLE_ARRAY_MEMBER]; };', the struct hack can be used with pre-C99 + compilers. When computing the size of such an object, don't use 'sizeof + (struct s)' as it overestimates the size. Use 'offsetof (struct s, d)' + instead. Don't use 'offsetof (struct s, d[0])', as this doesn't work with + MSVC and with C++ compilers. */ +#undef FLEXIBLE_ARRAY_MEMBER + /* float4 values are passed by value if 'true', by reference if 'false' */ #undef FLOAT4PASSBYVAL |