diff options
Diffstat (limited to 'config/c-compiler.m4')
| -rw-r--r-- | config/c-compiler.m4 | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/config/c-compiler.m4 b/config/c-compiler.m4 index 7d901e1f1aa..3321f226f3e 100644 --- a/config/c-compiler.m4 +++ b/config/c-compiler.m4 @@ -273,6 +273,30 @@ fi])# PGAC_C_BUILTIN_UNREACHABLE +# PGAC_C_COMPUTED_GOTO +# ----------------------- +# Check if the C compiler knows computed gotos (gcc extension, also +# available in at least clang). If so, define HAVE_COMPUTED_GOTO. +# +# Checking whether computed gotos are supported syntax-wise ought to +# be enough, as the syntax is otherwise illegal. +AC_DEFUN([PGAC_C_COMPUTED_GOTO], +[AC_CACHE_CHECK(for computed goto support, pgac_cv_computed_goto, +[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], +[[void *labeladdrs[] = {&&my_label}; + goto *labeladdrs[0]; + my_label: + return 1; +]])], +[pgac_cv_computed_goto=yes], +[pgac_cv_computed_goto=no])]) +if test x"$pgac_cv_computed_goto" = xyes ; then +AC_DEFINE(HAVE_COMPUTED_GOTO, 1, + [Define to 1 if your compiler handles computed gotos.]) +fi])# PGAC_C_COMPUTED_GOTO + + + # PGAC_C_VA_ARGS # -------------- # Check if the C compiler understands C99-style variadic macros, |