Turn off gcc-2.95's strict-alias optimization.

This, of course, should be only temporary.
From Andy Dougherty.

p4raw-id: //depot/metaconfig@4042

diff --git a/U/compline/ccflags.U b/U/compline/ccflags.U
index 6ae63b7..c1f32cf 100644 (file)
--- a/U/compline/ccflags.U
+++ b/U/compline/ccflags.U
@@ -91,7 +91,7 @@
 ?INIT:: no include file wanted by default
 ?INIT:inclwanted=''
 ?INIT:
-: determine optimize, if desired, or use for debug flag also
+: determine optimization, if desired, or use for debug flag also
 ?X: Allow for Configure -Uoptimize -- it's not strictly sensible, but
 ?X: it has happened and we know what they mean.   AD  2/16/98
 case "$optimize" in
@@ -101,11 +101,10 @@ case "$optimize" in
 esac
 $cat <<EOH
 
-Some C compilers have problems with their optimizers.  By default, $package
-compiles with the -O flag to use the optimizer.  Alternately, you might want
-to use the symbolic debugger, which uses the -g flag (on traditional Unix
-systems).  Either flag can be specified here.  To use neither flag, specify
-the word "none".
+By default, $package compiles with the -O flag to use the optimizer.
+Alternately, you might want to use the symbolic debugger, which uses
+the -g flag (on traditional Unix systems).  Either flag can be
+specified here.  To use neither flag, specify the word "none".
 
 EOH
 rp="What optimizer/debugger flag should be used?"
@@ -119,7 +118,7 @@ dflt=''
 : We will not override a previous value, but we might want to
 : augment a hint file
 case "$hint" in
-none|recommended)
+default|recommended)
        case "$gccversion" in
        1*) dflt='-fpcc-struct-return' ;;
        esac
@@ -135,6 +134,30 @@ none|recommended)
                fi
                ;;
        esac
+?X: If the user has gcc-2.95 or greater, try adding -fno-strict-alias.
+?X: Since the gcc "version" can be non-numeric, e.g.
+?X: "2.95.1 19990809 (prerelease)" , we'll do the test on any version
+?X: greater than 2.8.
+?X:    --Andy Dougherty  27 Aug 1999
+       case "$gccversion" in
+       1*) ;;
+       2.[0-8]*) ;;
+       *)      echo " "
+               echo "Checking if your compiler accepts -fno-strict-aliasing" 2>&1
+               echo 'int main(void) { return 0; }' > gcctest.c
+               if $cc -O2 -fno-strict-aliasing -o gcctest gcctest.c; then
+                       echo "Yes, it does." 2>&1
+                       case "$ccflags" in
+                       *strict-aliasing*) 
+                               echo "Leaving current flags $ccflags alone." 2>&1
+                               ;;
+                       *) dflt="$dflt -fno-strict-aliasing" ;;
+                       esac
+               else
+                       echo "Nope, it doesn't, but that's ok." 2>&1
+               fi
+               ;;
+       esac
        ;;
 esac
 
@@ -178,7 +201,7 @@ $define)
 esac
 
 case "$hint" in
-none|recommended) dflt="$ccflags $dflt" ;;
+default|recommended) dflt="$ccflags $dflt" ;;
 *) dflt="$ccflags";;
 esac
 

diff --git a/U/modified/cc.U b/U/modified/cc.U
index 67e8a51..4b0a4bb 100644 (file)
--- a/U/modified/cc.U
+++ b/U/modified/cc.U
@@ -98,10 +98,7 @@ fi
 if $test -f cc.cbu; then
     . ./cc.cbu
 fi
-?X: Check if they have gcc in any guise.  This is really only needed
-?X: if the user has version 1.x.x and needs -fpcc-struct-return.  Alas
-?X: BSD/386 ships a version of gcc 1.4.2 and calls it cc.  Hence the
-?X: paranoid test -- ADO.
+?X: Check if they have gcc in any guise.  
 echo " "
 echo "Checking for GNU cc in disguise and/or its version number..." >&4
 $cat >gccvers.c <<EOM