From 7544db951abbb5dca5373dcc7ae83ed60c0782ad Mon Sep 17 00:00:00 2001 From: Pedro Alves Date: Wed, 16 Dec 2015 22:56:48 +0000 Subject: [PATCH] Fix -Wno-unknown-warning support detection Ref: https://sourceware.org/ml/gdb/2015-12/msg00024.html We have code in configure.ac that tries to detect whether the compiler supports each warning and suppress it if not, but that doesn't work with "-Wno-" options, because gcc doesn't error out for -Wno-unknown-warning unless other diagnostics are being produced. See https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html. Handle this by checking whether -Wfoo works when we actually want -Wno-foo. gdb/ChangeLog: 2015-12-16 Pedro Alves * configure.ac (compiler warning flags): When testing a -Wno-foo option, check whether -Wfoo works instead. * configure: Regenerate. gdb/gdbserver/ChangeLog: 2015-12-16 Pedro Alves * configure.ac (compiler warning flags): When testing a -Wno-foo option, check whether -Wfoo works instead. * configure: Regenerate. --- gdb/ChangeLog | 6 ++++++ gdb/configure | 13 +++++++++++-- gdb/configure.ac | 13 +++++++++++-- gdb/gdbserver/ChangeLog | 6 ++++++ gdb/gdbserver/configure | 13 +++++++++++-- gdb/gdbserver/configure.ac | 13 +++++++++++-- 6 files changed, 56 insertions(+), 8 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index fcb0e3035fb..4d75eeaee24 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,9 @@ +2015-12-16 Pedro Alves + + * configure.ac (compiler warning flags): When testing a + -Wno-foo option, check whether -Wfoo works instead. + * configure: Regenerate. + 2015-12-16 Pedro Alves * common/vec.h (vec_offset): New macro. diff --git a/gdb/configure b/gdb/configure index 249a39975b0..4c308cb2c68 100755 --- a/gdb/configure +++ b/gdb/configure @@ -14376,14 +14376,23 @@ $as_echo_n "checking compiler warning flags... " >&6; } # Separate out the -Werror flag as some files just cannot be # compiled with it enabled. for w in ${build_warnings}; do + # GCC does not complain about -Wno-unknown-warning. Invert + # and test -Wunknown-warning instead. + case $w in + -Wno-*) + wtest=`echo $w | sed 's/-Wno-/-W/g'` ;; + *) + wtest=$w ;; + esac + case $w in -Werr*) WERROR_CFLAGS=-Werror ;; *) # Check whether GCC accepts it. saved_CFLAGS="$CFLAGS" - CFLAGS="$CFLAGS $w" + CFLAGS="$CFLAGS $wtest" saved_CXXFLAGS="$CXXFLAGS" - CXXFLAGS="$CXXFLAGS $w" + CXXFLAGS="$CXXFLAGS $wtest" cat confdefs.h - <<_ACEOF >conftest.$ac_ext /* end confdefs.h. */ diff --git a/gdb/configure.ac b/gdb/configure.ac index ebd797bf519..b9d8f8bca57 100644 --- a/gdb/configure.ac +++ b/gdb/configure.ac @@ -2007,14 +2007,23 @@ then # Separate out the -Werror flag as some files just cannot be # compiled with it enabled. for w in ${build_warnings}; do + # GCC does not complain about -Wno-unknown-warning. Invert + # and test -Wunknown-warning instead. + case $w in + -Wno-*) + wtest=`echo $w | sed 's/-Wno-/-W/g'` ;; + *) + wtest=$w ;; + esac + case $w in -Werr*) WERROR_CFLAGS=-Werror ;; *) # Check whether GCC accepts it. saved_CFLAGS="$CFLAGS" - CFLAGS="$CFLAGS $w" + CFLAGS="$CFLAGS $wtest" saved_CXXFLAGS="$CXXFLAGS" - CXXFLAGS="$CXXFLAGS $w" + CXXFLAGS="$CXXFLAGS $wtest" AC_TRY_COMPILE([],[],WARN_CFLAGS="${WARN_CFLAGS} $w",) CFLAGS="$saved_CFLAGS" CXXFLAGS="$saved_CXXFLAGS" diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog index 63bb2503a21..d54bb7404d9 100644 --- a/gdb/gdbserver/ChangeLog +++ b/gdb/gdbserver/ChangeLog @@ -1,3 +1,9 @@ +2015-12-16 Pedro Alves + + * configure.ac (compiler warning flags): When testing a + -Wno-foo option, check whether -Wfoo works instead. + * configure: Regenerate. + 2015-12-11 Don Breazeal * server.c (process_serial_event): Don't exit from gdbserver diff --git a/gdb/gdbserver/configure b/gdb/gdbserver/configure index ccb9639d520..ab03cacfe9f 100755 --- a/gdb/gdbserver/configure +++ b/gdb/gdbserver/configure @@ -6148,14 +6148,23 @@ $as_echo_n "checking compiler warning flags... " >&6; } # Separate out the -Werror flag as some files just cannot be # compiled with it enabled. for w in ${build_warnings}; do + # GCC does not complain about -Wno-unknown-warning. Invert + # and test -Wunknown-warning instead. + case $w in + -Wno-*) + wtest=`echo $w | sed 's/-Wno-/-W/g'` ;; + *) + wtest=$w ;; + esac + case $w in -Werr*) WERROR_CFLAGS=-Werror ;; *) # Check whether GCC accepts it. saved_CFLAGS="$CFLAGS" - CFLAGS="$CFLAGS $w" + CFLAGS="$CFLAGS $wtest" saved_CXXFLAGS="$CXXFLAGS" - CXXFLAGS="$CXXFLAGS $w" + CXXFLAGS="$CXXFLAGS $wtest" cat confdefs.h - <<_ACEOF >conftest.$ac_ext /* end confdefs.h. */ diff --git a/gdb/gdbserver/configure.ac b/gdb/gdbserver/configure.ac index 5524a052c61..6caf91c43a1 100644 --- a/gdb/gdbserver/configure.ac +++ b/gdb/gdbserver/configure.ac @@ -193,14 +193,23 @@ then # Separate out the -Werror flag as some files just cannot be # compiled with it enabled. for w in ${build_warnings}; do + # GCC does not complain about -Wno-unknown-warning. Invert + # and test -Wunknown-warning instead. + case $w in + -Wno-*) + wtest=`echo $w | sed 's/-Wno-/-W/g'` ;; + *) + wtest=$w ;; + esac + case $w in -Werr*) WERROR_CFLAGS=-Werror ;; *) # Check whether GCC accepts it. saved_CFLAGS="$CFLAGS" - CFLAGS="$CFLAGS $w" + CFLAGS="$CFLAGS $wtest" saved_CXXFLAGS="$CXXFLAGS" - CXXFLAGS="$CXXFLAGS $w" + CXXFLAGS="$CXXFLAGS $wtest" AC_TRY_COMPILE([],[],WARN_CFLAGS="${WARN_CFLAGS} $w",) CFLAGS="$saved_CFLAGS" CXXFLAGS="$saved_CXXFLAGS" -- 2.30.2