Merge branch 'develop' into feature/coding_standardsfeature/coding_standards

1 files changed, 98 insertions, 105 deletions

diff --git a/config/gnu-flags b/config/gnu-flags
index 6355ccf..fe6626d 100644
--- a/config/gnu-flags
+++ b/config/gnu-flags
@@ -7,7 +7,7 @@
 # This file is part of HDF5.  The full HDF5 copyright notice, including
 # terms governing use, modification, and redistribution, is contained in
 # the COPYING file, which can be found at the root of the source code
-# distribution tree, or in https://support.hdfgroup.org/ftp/HDF5/releases.
+# distribution tree, or in https://www.hdfgroup.org/licenses.
 # If you do not have access to either file, you may request a copy from
 # help@hdfgroup.org.
 
@@ -17,6 +17,38 @@
 # if the compiler is not GNU; otherwise 'cc_flags_set' is set to 'yes'
 #
 
+#
+# For now, do not promote any warnings to errors.
+#
+WARNINGS_AS_ERRORS_DFLT=no
+
+#
+# This filter rewrites -Werror= as -W, in that way demoting warnings
+# promoted to errors back to warnings, if WARNINGS_AS_ERRORS is no.
+#
+demote_errors()
+{
+    if [ ${WARNINGS_AS_ERRORS:-${WARNINGS_AS_ERRORS_DFLT}} = no ]; then
+        sed 's,-Werror=,-W,g'
+    else
+        cat
+    fi
+}
+
+#
+# Prepend `$srcdir/config/gnu-warnings/` to the filename suffix(es) given as
+# subroutine argument(s), remove comments starting with # and ending
+# at EOL, replace spans of whitespace (including newlines) with spaces,
+# and re-emit the file(s) thus filtered on the standard output stream.
+#
+load_gnu_arguments()
+{
+    set -- $(for arg; do
+        sed 's,#.*$,,' $srcdir/config/gnu-warnings/${arg} | demote_errors
+    done)
+    IFS=' ' echo "$*"
+}
+
 # Get the compiler version in a way that works for gcc
 # unless a compiler version is already known
 #
@@ -26,13 +58,13 @@
 if test "X-" = "X-$cc_flags_set"; then
     # PathScale compiler spits out gcc version string too. Need to
     # filter it out.
-    # icc beginning with version 12 includes a "gcc version compatiblilty"
+    # icc beginning with version 12 includes a "gcc version compatibility"
     # string, causing the gcc H5_CFLAGS to be erroneously added.  The line
     # "grep -v 'icc version'" causes the discarding of any output
     # containing 'icc version'.  The cc_version for icc is correctly determined
     # and flags added in the intel-flags script.
     cc_version="`$CC $CFLAGS $H5_CFLAGS -v 2>&1 | grep -v 'PathScale' |\
-        grep -v 'icc version' |\
+        grep -v '^icc.*version' |\
         grep 'gcc version' | sed 's/.*gcc version \([-a-z0-9\.]*\).*/\1/'`"
     cc_vendor=`echo $cc_version |sed 's/\([a-z]*\).*/\1/'`
     cc_version=`echo $cc_version |sed 's/[-a-z]//g'`
@@ -86,12 +118,16 @@ if test "X-gcc" = "X-$cc_vendor"; then
     esac
 
     case "$host_os-$host_cpu" in
-        # cygwin needs the "-std=c99" flag removed, so make
-        # a specific case for Cygwin without the flag and a default
-        # case to add the flag everywhere else
+        # Cygwin needs the "-std=c99" flag removed.
         cygwin-*)
             ;;
-
+        # On Solaris, gcc needs the gnu99 standard to pick up certain POSIX
+        # things. Do NOT use this as the gcc norm as this encourages the use
+        # of non-standard gcc extensions.
+        *solaris*)
+            H5_CFLAGS="$H5_CFLAGS -std=gnu99"
+            ;;
+        # Everybody else gets c99 as the standard.
         *)
             H5_CFLAGS="$H5_CFLAGS -std=c99"
             ;;
@@ -122,6 +158,15 @@ if test "X-gcc" = "X-$cc_vendor"; then
         DEBUG_CFLAGS="-ftrapv -fno-common"
     fi
 
+    ########################
+    # Enhanced Diagnostics #
+    ########################
+
+    if test $cc_vers_major -ge 10; then
+        NO_DIAGS_CFLAGS="-fdiagnostics-urls=never -fno-diagnostics-color"
+    fi
+    DIAGS_CFLAGS=
+
     ###########
     # Symbols #
     ###########
@@ -138,7 +183,7 @@ if test "X-gcc" = "X-$cc_vendor"; then
     ################
     # Optimization #
     ################
-    
+
     if test $cc_vers_major -le 4; then
         HIGH_OPT_CFLAGS="-O3"
         DEBUG_OPT_CFLAGS=
@@ -156,136 +201,83 @@ if test "X-gcc" = "X-$cc_vendor"; then
     # General #
     ###########
 
-    # Note that some of the flags listed here really should be developer
-    # flags (listed in a separate variable, below) but we put them here
-    # because they are not raised by the current code and we'd like to
-    # know if they do start showing up.
-    #
-    # NOTE: Don't add -Wpadded here since we can't/won't fix the (many)
-    # warnings that are emitted. If you need it, add it from the
-    # environment variable at configure time.
-    #
-    # NOTE: Disable the -Wformat-nonliteral from -Wformat=2 here and re-add
-    # it to the developer flags.
-    #
-    H5_CFLAGS="$H5_CFLAGS -pedantic -Wall -Wextra -Wbad-function-cast -Wc++-compat -Wcast-align"
-    H5_CFLAGS="$H5_CFLAGS -Wcast-qual -Wconversion -Wdeclaration-after-statement -Wdisabled-optimization -Wfloat-equal"
-    H5_CFLAGS="$H5_CFLAGS -Wformat=2 -Wno-format-nonliteral -Winit-self -Winvalid-pch -Wmissing-declarations -Wmissing-include-dirs"
-    H5_CFLAGS="$H5_CFLAGS -Wmissing-prototypes -Wnested-externs -Wold-style-definition -Wpacked"
-    H5_CFLAGS="$H5_CFLAGS -Wredundant-decls -Wshadow -Wstrict-prototypes -Wswitch-enum -Wswitch-default"
-    H5_CFLAGS="$H5_CFLAGS -Wundef -Wunused-macros -Wunsafe-loop-optimizations -Wwrite-strings"
-
-    ######################
-    # Developer warnings #
-    ######################
-
-    # (suggestions from gcc, not code problems)
-    # NOTE: -Wformat-nonliteral added back in here (from being disabled in H5_CFLAGS)
-    DEVELOPER_WARNING_CFLAGS="-Winline -Waggregate-return -Wmissing-format-attribute -Wmissing-noreturn -Wformat-nonliteral"
-    NO_DEVELOPER_WARNING_CFLAGS="-Wno-inline -Wno-aggregate-return -Wno-missing-format-attribute -Wno-missing-noreturn"
-
-    #######################
-    # gcc 4 special cases #
-    #######################
+    # Add various general warning flags in gnu-warnings for gcc versions 4.8 and later.
+    if test $cc_vers_major -eq 4 -a $cc_vers_minor -ge 8 -o $cc_vers_major -gt 4; then
+        H5_CFLAGS="$H5_CFLAGS $(load_gnu_arguments general)"
+        H5_ECFLAGS="$H5_ECFLAGS $(load_gnu_arguments error-general)"
 
-    # Disable warnings about using the 'long long' type w/ gcc 4.6 and earlier
-    if test $cc_vers_major -eq 4 -a $cc_vers_minor -ge 2 -o $cc_vers_major -eq 4 -a $cc_vers_minor -le 6; then
-        H5_CFLAGS="$H5_CFLAGS -Wno-long-long"
-    fi
+        ######################
+        # Developer warnings #
+        ######################
 
-    # -Wvolatile-register-var was later incorporated into -Wall and              
-    # only needs to be specified explicitly for gcc 4.2-4.3                      
-    if test $cc_vers_major -eq 4 -a $cc_vers_minor -ge 2 -o $cc_vers_major -eq 4 -a $cc_vers_minor -le 3; then
-        H5_CFLAGS="$H5_CFLAGS -Wvolatile-register-var"                           
-    fi 
+        NO_DEVELOPER_WARNING_CFLAGS=$(load_gnu_arguments no-developer-general)
+        DEVELOPER_WARNING_CFLAGS=$(load_gnu_arguments developer-general)
 
-    # -Wstrict-aliasing was later incorporated into -Wall and
-    # only needs to be specified explicitly for gcc 4.5-4.6
-    if test $cc_vers_major -eq 4 -a $cc_vers_minor -ge 5 -o $cc_vers_major -eq 4 -a $cc_vers_minor -le 6; then
-        H5_CFLAGS="$H5_CFLAGS -Wstrict-aliasing"
     fi
 
-    # The non-valued form of -Wstrict-overflow is used in gcc 4.2-4.4
-    if test $cc_vers_major -eq 4 -a $cc_vers_minor -ge 2 -a $cc_vers_major -eq 4 -a $cc_vers_minor -le 4; then
-        H5_CFLAGS="$H5_CFLAGS -Wstrict-overflow"
-    fi
+    #######################
+    # gcc 4 special cases #
+    #######################
 
-    # -Wvla was later incorporated into -Wpedantic and
-    # only needs to be specified explicitly for gcc 4
-    if test $cc_vers_major -eq 4 -a $cc_vers_minor -ge 2; then
-        H5_CFLAGS="$H5_CFLAGS -Wvla"
+    # GCC 4.8 through the end of GCC 4 series
+    if test $cc_vers_major -eq 4 -a $cc_vers_minor -ge 8; then
+        H5_CFLAGS="$H5_CFLAGS $(load_gnu_arguments 4.8-4.last)"
     fi
 
     #############################
     # Version-specific warnings #
     #############################
 
-    # gcc 4.3                                                                    
-    if test $cc_vers_major -ge 5 -o $cc_vers_major -eq 4 -a $cc_vers_minor -ge 3; then
-        H5_CFLAGS="$H5_CFLAGS -Wlogical-op -Wlarger-than=2560"                   
-    fi 
-
-    # gcc 4.4
-    if test $cc_vers_major -ge 5 -o $cc_vers_major -eq 4 -a $cc_vers_minor -ge 4; then
-        H5_CFLAGS="$H5_CFLAGS -Wsync-nand -Wframe-larger-than=16384 -Wpacked-bitfield-compat"
-    fi
-
-    # gcc 4.5
-    if test $cc_vers_major -ge 5 -o $cc_vers_major -eq 4 -a $cc_vers_minor -ge 5; then
-        H5_CFLAGS="$H5_CFLAGS -Wstrict-overflow=5 -Wjump-misses-init -Wunsuffixed-float-constants"
-    fi
-
-    # gcc 4.6
-    if test $cc_vers_major -ge 5 -o $cc_vers_major -eq 4 -a $cc_vers_minor -ge 6; then
-        H5_CFLAGS="$H5_CFLAGS -Wdouble-promotion -Wtrampolines"
-        DEVELOPER_WARNING_CFLAGS="$DEVELOPER_WARNING_CFLAGS -Wsuggest-attribute=const"
-        NO_DEVELOPER_WARNING_CFLAGS="$NO_DEVELOPER_WARNING_CFLAGS -Wno-suggest-attribute=const"
-    fi
-
-    # gcc 4.7
-    if test $cc_vers_major -ge 5 -o $cc_vers_major -eq 4 -a $cc_vers_minor -ge 7; then
-        H5_CFLAGS="$H5_CFLAGS -Wstack-usage=8192 -Wvector-operation-performance"
-        DEVELOPER_WARNING_CFLAGS="$DEVELOPER_WARNING_CFLAGS -Wsuggest-attribute=pure -Wsuggest-attribute=noreturn"
-        NO_DEVELOPER_WARNING_CFLAGS="$NO_DEVELOPER_WARNING_CFLAGS -Wno-suggest-attribute=pure -Wno-suggest-attribute=noreturn"
-    fi
-
-    # gcc 4.8
+    # gcc >= 4.8
     if test $cc_vers_major -ge 5 -o $cc_vers_major -eq 4 -a $cc_vers_minor -ge 8; then
-        DEVELOPER_WARNING_CFLAGS="$DEVELOPER_WARNING_CFLAGS -Wsuggest-attribute=format"
-        NO_DEVELOPER_WARNING_CFLAGS="$NO_DEVELOPER_WARNING_CFLAGS -Wno-suggest-attribute=format"
+        H5_CFLAGS="$H5_CFLAGS $(load_gnu_arguments 4.8)"
+        DEVELOPER_WARNING_CFLAGS="$DEVELOPER_WARNING_CFLAGS $(load_gnu_arguments developer-4.8)"
+        NO_DEVELOPER_WARNING_CFLAGS="$NO_DEVELOPER_WARNING_CFLAGS $(load_gnu_arguments no-developer-4.8)"
     fi
 
-    # gcc 4.9
+    # gcc >= 4.9
     if test $cc_vers_major -ge 5 -o $cc_vers_major -eq 4 -a $cc_vers_minor -ge 9; then
-        H5_CFLAGS="$H5_CFLAGS -Wdate-time"
+        H5_CFLAGS="$H5_CFLAGS $(load_gnu_arguments 4.9)"
     fi
 
-    # gcc 5
+    # gcc >= 5
     if test $cc_vers_major -ge 5; then
-        H5_CFLAGS="$H5_CFLAGS -Warray-bounds=2 -Wc99-c11-compat"
+        H5_CFLAGS="$H5_CFLAGS $(load_gnu_arguments 5)"
+        H5_ECFLAGS="$H5_ECFLAGS $(load_gnu_arguments error-5)"
     fi
 
-    # gcc 6
+    # gcc >= 6
     if test $cc_vers_major -ge 6; then
-        H5_CFLAGS="$H5_CFLAGS -Wnull-dereference -Wunused-const-variable -Wduplicated-cond -Whsa -Wnormalized"
+        H5_CFLAGS="$H5_CFLAGS $(load_gnu_arguments 6)"
     fi
 
-    # gcc 7
+    # gcc >= 7
     if test $cc_vers_major -ge 7; then
-        DEVELOPER_WARNING_CFLAGS="$DEVELOPER_WARNING_CFLAGS -Wstringop-overflow=2"
-        H5_CFLAGS="$H5_CFLAGS -Walloc-zero -Walloca -Wduplicated-branches -Wformat-overflow=2 -Wformat-truncation=2 -Wimplicit-fallthrough=5 -Wrestrict"
+        H5_CFLAGS="$H5_CFLAGS $(load_gnu_arguments 7)"
+        DEVELOPER_WARNING_CFLAGS="$DEVELOPER_WARNING_CFLAGS $(load_gnu_arguments developer-7)"
     fi
 
     # gcc 8
     if test $cc_vers_major -ge 8; then
-        DEVELOPER_WARNING_CFLAGS="$DEVELOPER_WARNING_CFLAGS -Wstringop-overflow=4 -Wsuggest-attribute=cold -Wsuggest-attribute=malloc"
-        NO_DEVELOPER_WARNING_CFLAGS="$NO_DEVELOPER_WARNING_CFLAGS -Wno-suggest-attribute=cold -Wno-suggest-attribute=malloc"
-        H5_CFLAGS="$H5_CFLAGS -Wattribute-alias -Wcast-align=strict -Wshift-overflow=2"
+        H5_CFLAGS="$H5_CFLAGS $(load_gnu_arguments 8)"
+        H5_ECFLAGS="$H5_ECFLAGS $(load_gnu_arguments error-8)"
+        DEVELOPER_WARNING_CFLAGS="$DEVELOPER_WARNING_CFLAGS $(load_gnu_arguments developer-8)"
+        NO_DEVELOPER_WARNING_CFLAGS="$NO_DEVELOPER_WARNING_CFLAGS $(load_gnu_arguments no-developer-8)"
     fi
 
     # gcc 9
     if test $cc_vers_major -ge 9; then
-        H5_CFLAGS="$H5_CFLAGS -Wattribute-alias=2 -Wmissing-profile"
+        H5_CFLAGS="$H5_CFLAGS $(load_gnu_arguments 9)"
+    fi
+
+    # gcc >= 9.3
+    if test $cc_vers_major -ge 10 -o $cc_vers_major -eq 9 -a $cc_vers_minor -ge 3; then
+        H5_CFLAGS="$H5_CFLAGS $(load_gnu_arguments 9.3)"
+    fi
+
+    # gcc >= 10
+    if test $cc_vers_major -ge 10; then
+        DEVELOPER_WARNING_CFLAGS="$DEVELOPER_WARNING_CFLAGS $(load_gnu_arguments developer-10)"
     fi
 
     #################
@@ -299,3 +291,4 @@ if test "X$cc_flags_set" = "X"; then
     cc_vendor=
     cc_version=
 fi
+