INN commit: branches/2.6 (configure.ac m4/cc-flags.m4)

[INN Commit]

    Date: Tuesday, December 1, 2020 @ 13:10:12
  Author: iulius
Revision: 10434

Fix build issue in linker feature probing

Thanks to Bo Lindbergh for the report.

Modified:
  branches/2.6/configure.ac
  branches/2.6/m4/cc-flags.m4

----------------+
 configure.ac   |    7 ++++---
 m4/cc-flags.m4 |   27 +++++++++++++++++++++++----
 2 files changed, 27 insertions(+), 7 deletions(-)

Modified: configure.ac
===================================================================
--- configure.ac	2020-12-01 21:08:53 UTC (rev 10433)
+++ configure.ac	2020-12-01 21:10:12 UTC (rev 10434)
@@ -616,14 +616,15 @@
 AS_IF([test x"$inn_enable_hardening_flags" = xyes],
     [INN_PROG_CC_FLAG([-fPIE], [CFLAGS="${CFLAGS} -fPIE"
                                 CC_WARNINGS="${CC_WARNINGS} -fPIE"
-                                LDFLAGS="${LDFLAGS} -fPIE -pie"], [])
+                                INN_PROG_LD_FLAG([-pie],
+                                    [LDFLAGS="${LDFLAGS} -pie"], [])])
      INN_PROG_CC_FLAG([-fstack-protector-strong],
                       [CFLAGS="${CFLAGS} -fstack-protector-strong"
                        CC_WARNINGS="${CC_WARNINGS} -fstack-protector-strong"],
                       [])
-     INN_PROG_CC_FLAG([-Wl,-z,relro],
+     INN_PROG_LD_FLAG([-Wl,-z,relro],
                       [LDFLAGS="${LDFLAGS} -Wl,-z,relro"], [])
-     INN_PROG_CC_FLAG([-Wl,-z,now],
+     INN_PROG_LD_FLAG([-Wl,-z,now],
                       [LDFLAGS="${LDFLAGS} -Wl,-z,now"], [])])
 
 dnl Clean up our LIBS, just for grins.

Modified: m4/cc-flags.m4
===================================================================
--- m4/cc-flags.m4	2020-12-01 21:08:53 UTC (rev 10433)
+++ m4/cc-flags.m4	2020-12-01 21:10:12 UTC (rev 10434)
@@ -1,9 +1,10 @@
 dnl Check whether the compiler supports particular flags.
 dnl $Id$
 dnl
-dnl Provides INN_PROG_CC_FLAG, which checks whether a compiler supports a
-dnl given flag.  If it does, the commands in the second argument are run.  If
-dnl not, the commands in the third argument are run.
+dnl Provides INN_PROG_CC_FLAG and INN_PROG_LD_FLAG, which checks whether a
+dnl compiler supports a given flag for either compilation or linking,
+dnl respectively.  If it does, the commands in the second argument are run.
+dnl If not, the commands in the third argument are run.
 dnl
 dnl The canonical version of this file is maintained in the rra-c-util
 dnl package, available at <https://www.eyrie.org/~eagle/software/rra-c-util/>.
@@ -29,8 +30,11 @@
 dnl Used to build the result cache name.
 AC_DEFUN([_INN_PROG_CC_FLAG_CACHE],
 [translit([inn_cv_compiler_c_$1], [-=+,], [____])])
+AC_DEFUN([_INN_PROG_LD_FLAG_CACHE],
+[translit([inn_cv_linker_c_$1], [-=+,], [____])])
 
-dnl Check whether a given flag is supported by the compiler.
+dnl Check whether a given flag is supported by the compiler when compiling a C
+dnl source file.
 AC_DEFUN([INN_PROG_CC_FLAG],
 [AC_REQUIRE([AC_PROG_CC])
  AC_MSG_CHECKING([if $CC supports $1])
@@ -46,3 +50,18 @@
  AC_MSG_RESULT([$_INN_PROG_CC_FLAG_CACHE([$1])])
  AS_IF([test x"$_INN_PROG_CC_FLAG_CACHE([$1])" = xyes], [$2], [$3])])
 
+dnl Check whether a given flag is supported by the compiler when linking an
+dnl executable.
+AC_DEFUN([INN_PROG_LD_FLAG],
+[AC_REQUIRE([AC_PROG_CC])
+ AC_MSG_CHECKING([if $CC supports $1 for linking])
+ AC_CACHE_VAL([_INN_PROG_LD_FLAG_CACHE([$1])],
+    [save_LDFLAGS=$LDFLAGS
+     LDFLAGS="$LDFLAGS $1"
+     AC_LINK_IFELSE([AC_LANG_PROGRAM([], [int foo = 0;])],
+        [_INN_PROG_LD_FLAG_CACHE([$1])=yes],
+        [_INN_PROG_LD_FLAG_CACHE([$1])=no])
+     LDFLAGS=$save_LDFLAGS])
+ AC_MSG_RESULT([$_INN_PROG_LD_FLAG_CACHE([$1])])
+ AS_IF([test x"$_INN_PROG_LD_FLAG_CACHE([$1])" = xyes], [$2], [$3])])
+