Don't add general warnings flags for unsupported old versions of gcc and

g++ (older than gcc/g++ 4.2).
Correct gnu-cxxflags to determine warnings flags to be added based on
C++ compiler version instead of C compiler version.

4 files changed, 53 insertions, 41 deletions

diff --git a/config/cmake/HDFCXXCompilerFlags.cmake b/config/cmake/HDFCXXCompilerFlags.cmake
index 6aa8784..721fca4 100644
--- a/config/cmake/HDFCXXCompilerFlags.cmake
+++ b/config/cmake/HDFCXXCompilerFlags.cmake
@@ -103,8 +103,10 @@ if (NOT MSVC)
         list (APPEND H5_CXXFLAGS0 "-Wsign-compare -Wtrigraphs -Wwrite-strings")
       endif()
     elseif (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
-      if (CMAKE_COMPILER_IS_GNUCXX AND CMAKE_CXX_COMPILER_LOADED)
-        # autotools always add the C flags with the CXX flags
+      if (CMAKE_COMPILER_IS_GNUCXX AND CMAKE_CXX_COMPILER_LOADED 
+          AND NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.2)
+        # autotools always add the C flags with the CXX flags, except for 
+        # with older versions that are no longer supported
         ADD_H5_FLAGS (HDF5_CMAKE_CXX_FLAGS "${HDF5_SOURCE_DIR}/config/gnu-warnings/general")
         ADD_H5_FLAGS (HDF5_CMAKE_CXX_FLAGS "${HDF5_SOURCE_DIR}/config/gnu-warnings/cxx-general")
       endif ()
@@ -141,16 +143,17 @@ if (NOT MSVC)
   endif ()
 
   if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
-    # Append warning flags that only gcc 4.3+ knows about
-    # autotools always add the C flags with the CXX flags
-    ADD_H5_FLAGS (H5_CXXFLAGS1 "${HDF5_SOURCE_DIR}/config/gnu-warnings/4.3")
-    #
     # Technically, variable-length arrays are part of the C99 standard, but
     #   we should approach them a bit cautiously... Only needed for gcc 4.X
-    if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 5.0)
+    if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 5.0 AND NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 4.2)
       # autotools always add the C flags with the CXX flags
       ADD_H5_FLAGS (H5_CXXFLAGS1 "${HDF5_SOURCE_DIR}/config/gnu-warnings/4.2-4.last")
     endif ()
+    # Append warning flags that only gcc 4.3+ knows about
+    # autotools always add the C flags with the CXX flags
+    if (CMAKE_C_COMPILER_VERSION VERSION_LESS 4.3 AND NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 4.2)
+      ADD_H5_FLAGS (H5_CXXFLAGS1 "${HDF5_SOURCE_DIR}/config/gnu-warnings/4.3")
+    endif()
 
     # Append more extra warning flags that only gcc 4.4+ know about
     if (NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.4)
@@ -172,7 +175,7 @@ if (NOT MSVC)
     endif ()
 
     # Append more extra warning flags that only gcc 4.6 and less know about
-    if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.7)
+    if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.7 AND NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 4.2)
       # autotools always add the C flags with the CXX flags
       ADD_H5_FLAGS (H5_CXXFLAGS1 "${HDF5_SOURCE_DIR}/config/gnu-warnings/4.2-4.6")
     endif ()
diff --git a/config/cmake/HDFCompilerFlags.cmake b/config/cmake/HDFCompilerFlags.cmake
index 72141c0..a40b525 100644
--- a/config/cmake/HDFCompilerFlags.cmake
+++ b/config/cmake/HDFCompilerFlags.cmake
@@ -111,8 +111,11 @@ if (NOT MSVC)
         list (APPEND H5_CFLAGS0 "-Wsign-compare -Wtrigraphs -Wwrite-strings")
       endif()
     elseif (CMAKE_C_COMPILER_ID STREQUAL "GNU")
-      ADD_H5_FLAGS (HDF5_CMAKE_C_FLAGS "${HDF5_SOURCE_DIR}/config/gnu-warnings/general")
-      ADD_H5_FLAGS (H5_CFLAGS0 "${HDF5_SOURCE_DIR}/config/gnu-warnings/error-general")
+      # Add general CFlags except for older versions that are no longer supported
+      if (NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 4.2)
+        ADD_H5_FLAGS (HDF5_CMAKE_C_FLAGS "${HDF5_SOURCE_DIR}/config/gnu-warnings/general")
+        ADD_H5_FLAGS (H5_CFLAGS0 "${HDF5_SOURCE_DIR}/config/gnu-warnings/error-general")
+      endif ()
       # gcc automatically inlines based on the optimization level
       # this is just a failsafe
       list (APPEND H5_CFLAGS0 "-finline-functions")
@@ -149,14 +152,16 @@ if (NOT MSVC)
 
 
   if (CMAKE_C_COMPILER_ID STREQUAL "GNU")
-    # Append warning flags that only gcc 4.3+ knows about
-    ADD_H5_FLAGS (H5_CFLAGS1 "${HDF5_SOURCE_DIR}/config/gnu-warnings/4.3")
-    #
     # Technically, variable-length arrays are part of the C99 standard, but
     #   we should approach them a bit cautiously... Only needed for gcc 4.X
-    if (CMAKE_C_COMPILER_VERSION VERSION_LESS 5.0)
+    if (CMAKE_C_COMPILER_VERSION VERSION_LESS 5.0 AND NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 4.2)
       ADD_H5_FLAGS (H5_CFLAGS1 "${HDF5_SOURCE_DIR}/config/gnu-warnings/4.2-4.last")
     endif ()
+    # Append warning flags that only gcc 4.3+ knows about
+    if (CMAKE_C_COMPILER_VERSION VERSION_LESS 4.3 AND NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 4.2)
+      ADD_H5_FLAGS (H5_CFLAGS1 "${HDF5_SOURCE_DIR}/config/gnu-warnings/4.3")
+    endif ()
+
 
     # Append more extra warning flags that only gcc 4.4+ know about
     if (NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 4.4)
@@ -174,7 +179,7 @@ if (NOT MSVC)
     endif ()
 
     # Append more extra warning flags that only gcc 4.6 and less know about
-    if (CMAKE_C_COMPILER_VERSION VERSION_LESS 4.7)
+    if (CMAKE_C_COMPILER_VERSION VERSION_LESS 4.7 AND NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 4.2)
       ADD_H5_FLAGS (H5_CFLAGS1 "${HDF5_SOURCE_DIR}/config/gnu-warnings/4.2-4.6")
     endif ()
 
diff --git a/config/gnu-cxxflags b/config/gnu-cxxflags
index e177aef..b3b082d 100644
--- a/config/gnu-cxxflags
+++ b/config/gnu-cxxflags
@@ -79,9 +79,9 @@ if test "X-" = "X-$cxx_flags_set"; then
     cxx_vers_major=`echo $cxx_version | cut -f1 -d.`
     cxx_vers_minor=`echo $cxx_version | cut -f2 -d.`
     cxx_vers_patch=`echo $cxx_version | cut -f3 -d.`
-    test -n "$cc_vers_major" || cxx_vers_major=0
-    test -n "$cc_vers_minor" || cxx_vers_minor=0
-    test -n "$cc_vers_patch" || cxx_vers_patch=0
+    test -n "$cxx_vers_major" || cxx_vers_major=0
+    test -n "$cxx_vers_minor" || cxx_vers_minor=0
+    test -n "$cxx_vers_patch" || cxx_vers_patch=0
     cxx_vers_all=`expr $cxx_vers_major '*' 1000000 + $cxx_vers_minor '*' 1000 + $cxx_vers_patch`
 fi
 
@@ -180,10 +180,12 @@ if test "X-g++" = "X-$cxx_vendor"; then
     # General #
     ###########
 
-    H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments general)"
-    H5_ECXXFLAGS="$H5_ECXXFLAGS $(load_gnu_arguments error-general)"
-    H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments cxx-general)"
-    #H5_ECXXFLAGS="$H5_ECXXFLAGS $(load_gnu_arguments error-cxx-general)"
+    if test $cxx_vers_major -eq 4 -a $cxx_vers_minor -ge 2 -o $cxx_vers_major -gt 4; then
+        H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments general)"
+        H5_ECXXFLAGS="$H5_ECXXFLAGS $(load_gnu_arguments error-general)"
+        H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments cxx-general)"
+        #H5_ECXXFLAGS="$H5_ECXXFLAGS $(load_gnu_arguments error-cxx-general)"
+    fi
 
     ######################
     # Developer warnings #
@@ -197,27 +199,27 @@ if test "X-g++" = "X-$cxx_vendor"; then
     #######################
 
     # GCC 4.2 through 4.6
-    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
+    if test $cxx_vers_major -eq 4 -a $cxx_vers_minor -ge 2 -o $cxx_vers_major -eq 4 -a $cxx_vers_minor -le 6; then
         H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments 4.2-4.6)"
     fi
 
     # GCC 4.2 through 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
+    if test $cxx_vers_major -eq 4 -a $cxx_vers_minor -ge 2 -o $cxx_vers_major -eq 4 -a $cxx_vers_minor -le 3; then
         H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments 4.2-4.3)"
     fi
 
     # GCC 4.5 through 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
+    if test $cxx_vers_major -eq 4 -a $cxx_vers_minor -ge 5 -o $cxx_vers_major -eq 4 -a $cxx_vers_minor -le 6; then
         H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments 4.5-4.6)"
     fi
 
     # GCC 4.2 through 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
+    if test $cxx_vers_major -eq 4 -a $cxx_vers_minor -ge 2 -a $cxx_vers_major -eq 4 -a $cxx_vers_minor -le 4; then
         H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments 4.2-4.4)"
     fi
 
     # GCC 4.2 through the end of GCC 4 series
-    if test $cc_vers_major -eq 4 -a $cc_vers_minor -ge 2; then
+    if test $cxx_vers_major -eq 4 -a $cxx_vers_minor -ge 2; then
         H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments 4.2-4.last)"
     fi
 
@@ -226,68 +228,68 @@ if test "X-g++" = "X-$cxx_vendor"; then
     #############################
 
     # gcc >= 4.3
-    if test $cc_vers_major -ge 5 -o $cc_vers_major -eq 4 -a $cc_vers_minor -ge 3; then
+    if test $cxx_vers_major -ge 5 -o $cxx_vers_major -eq 4 -a $cxx_vers_minor -ge 3; then
         H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments 4.3)"
     fi
 
     # gcc >= 4.4
-    if test $cc_vers_major -ge 5 -o $cc_vers_major -eq 4 -a $cc_vers_minor -ge 4; then
+    if test $cxx_vers_major -ge 5 -o $cxx_vers_major -eq 4 -a $cxx_vers_minor -ge 4; then
         H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments 4.4)"
     fi
 
     # gcc >= 4.5
-    if test $cc_vers_major -ge 5 -o $cc_vers_major -eq 4 -a $cc_vers_minor -ge 5; then
+    if test $cxx_vers_major -ge 5 -o $cxx_vers_major -eq 4 -a $cxx_vers_minor -ge 5; then
         H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments 4.5)"
     DEVELOPER_WARNING_CXXFLAGS="$DEVELOPER_WARNING_CXXFLAGS $(load_gnu_arguments developer-4.5)"
     NO_DEVELOPER_WARNING_CXXFLAGS="$NO_DEVELOPER_WARNING_CXXFLAGS $(load_gnu_arguments no-developer-4.5)"
     fi
 
     # gcc >= 4.6
-    if test $cc_vers_major -ge 5 -o $cc_vers_major -eq 4 -a $cc_vers_minor -ge 6; then
+    if test $cxx_vers_major -ge 5 -o $cxx_vers_major -eq 4 -a $cxx_vers_minor -ge 6; then
         H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments 4.6)"
     DEVELOPER_WARNING_CXXFLAGS="$DEVELOPER_WARNING_CXXFLAGS $(load_gnu_arguments developer-4.6)"
     NO_DEVELOPER_WARNING_CXXFLAGS="$NO_DEVELOPER_WARNING_CXXFLAGS $(load_gnu_arguments no-developer-4.6)"
     fi
 
     # gcc >= 4.7
-    if test $cc_vers_major -ge 5 -o $cc_vers_major -eq 4 -a $cc_vers_minor -ge 7; then
+    if test $cxx_vers_major -ge 5 -o $cxx_vers_major -eq 4 -a $cxx_vers_minor -ge 7; then
         H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments 4.7)"
     DEVELOPER_WARNING_CXXFLAGS="$DEVELOPER_WARNING_CXXFLAGS $(load_gnu_arguments developer-4.7)"
     NO_DEVELOPER_WARNING_CXXFLAGS="$NO_DEVELOPER_WARNING_CXXFLAGS $(load_gnu_arguments no-developer-4.7)"
     fi
 
     # gcc >= 4.8
-    if test $cc_vers_major -ge 5 -o $cc_vers_major -eq 4 -a $cc_vers_minor -ge 8; then
+    if test $cxx_vers_major -ge 5 -o $cxx_vers_major -eq 4 -a $cxx_vers_minor -ge 8; then
         H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments 4.8)"
     DEVELOPER_WARNING_CXXFLAGS="$DEVELOPER_WARNING_CXXFLAGS $(load_gnu_arguments developer-4.8)"
     NO_DEVELOPER_WARNING_CXXFLAGS="$NO_DEVELOPER_WARNING_CXXFLAGS $(load_gnu_arguments no-developer-4.8)"
     fi
 
     # gcc >= 4.9
-    if test $cc_vers_major -ge 5 -o $cc_vers_major -eq 4 -a $cc_vers_minor -ge 9; then
+    if test $cxx_vers_major -ge 5 -o $cxx_vers_major -eq 4 -a $cxx_vers_minor -ge 9; then
         H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments 4.9)"
         H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments cxx-4.9)"
     fi
 
     # gcc >= 5
-    if test $cc_vers_major -ge 5; then
+    if test $cxx_vers_major -ge 5; then
         H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments 5)"
         H5_ECXXFLAGS="$H5_ECXXFLAGS $(load_gnu_arguments error-5)"
     fi
 
     # gcc >= 6
-    if test $cc_vers_major -ge 6; then
+    if test $cxx_vers_major -ge 6; then
         H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments 6)"
     fi
 
     # gcc >= 7
-    if test $cc_vers_major -ge 7; then
+    if test $cxx_vers_major -ge 7; then
         H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments 7)"
     DEVELOPER_WARNING_CXXFLAGS="$DEVELOPER_WARNING_CXXFLAGS $(load_gnu_arguments developer-7)"
     fi
 
     # gcc 8
-    if test $cc_vers_major -ge 8; then
+    if test $cxx_vers_major -ge 8; then
         H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments 8)"
         H5_ECXXFLAGS="$H5_ECXXFLAGS $(load_gnu_arguments error-8)"
     DEVELOPER_WARNING_CXXFLAGS="$DEVELOPER_WARNING_CXXFLAGS $(load_gnu_arguments developer-8)"
@@ -295,7 +297,7 @@ if test "X-g++" = "X-$cxx_vendor"; then
     fi
 
     # gcc 9
-    if test $cc_vers_major -ge 9; then
+    if test $cxx_vers_major -ge 9; then
         H5_CXXFLAGS="$H5_CXXFLAGS $(load_gnu_arguments 9)"
     fi
 
diff --git a/config/gnu-flags b/config/gnu-flags
index ad07552..dba9324 100644
--- a/config/gnu-flags
+++ b/config/gnu-flags
@@ -188,8 +188,10 @@ if test "X-gcc" = "X-$cc_vendor"; then
     # General #
     ###########
 
-    H5_CFLAGS="$H5_CFLAGS $(load_gnu_arguments general)"
-    H5_ECFLAGS="$H5_ECFLAGS $(load_gnu_arguments error-general)"
+    if test $cc_vers_major -eq 4 -a $cc_vers_minor -ge 2 -o $cc_vers_major -gt 4; then
+        H5_CFLAGS="$H5_CFLAGS $(load_gnu_arguments general)"
+        H5_ECFLAGS="$H5_ECFLAGS $(load_gnu_arguments error-general)"
+    fi
 
     ######################
     # Developer warnings #