configure: replace -Os with equivalent based on -O2

[musl] / configure

diff --git a/configure b/configure
index a5231a0..0b966ed 100755 (executable)
--- a/configure
+++ b/configure
@@ -353,6 +353,14 @@ tryflag CFLAGS_C99FSE -fexcess-precision=standard \
 || { test "$ARCH" = i386 && tryflag CFLAGS_C99FSE -ffloat-store ; }
 tryflag CFLAGS_C99FSE -frounding-math
 
+#
+# Semantically we want to insist that our sources follow the
+# C rules for type-based aliasing, but most if not all real-world
+# compilers are known or suspected to have critical bugs in their
+# type-based aliasing analysis. See for example GCC bug 107107.
+#
+tryflag CFLAGS_C99FSE -fno-strict-aliasing
+
 #
 # We may use the may_alias attribute if __GNUC__ is defined, so
 # if the compiler defines __GNUC__ but does not provide it,
@@ -409,7 +417,7 @@ test "$debug" = yes && CFLAGS_AUTO=-g
 #
 printf "checking whether we should preprocess assembly to add debugging information... "
 if fnmatch '-g*|*\ -g*' "$CFLAGS_AUTO $CFLAGS" &&
-   test -f "tools/add-cfi.$ARCH.awk" &&
+   test -f "$srcdir/tools/add-cfi.$ARCH.awk" &&
    printf ".file 1 \"srcfile.s\"\n.line 1\n.cfi_startproc\n.cfi_endproc" | $CC -g -x assembler -c -o /dev/null 2>/dev/null -
 then
   ADD_CFI=yes
@@ -436,7 +444,20 @@ xno|x) printf "disabled\n" ; optimize=no ;;
 *) printf "custom\n" ;;
 esac
 
-test "$optimize" = no || tryflag CFLAGS_AUTO -Os || tryflag CFLAGS_AUTO -O2
+if test "$optimize" = no ; then :
+else
+tryflag CFLAGS_AUTO -O2
+tryflag CFLAGS_AUTO -fno-align-jumps
+tryflag CFLAGS_AUTO -fno-align-functions
+tryflag CFLAGS_AUTO -fno-align-loops
+tryflag CFLAGS_AUTO -fno-align-labels
+tryflag CFLAGS_AUTO -fira-region=one
+tryflag CFLAGS_AUTO -fira-hoist-pressure
+tryflag CFLAGS_AUTO -freorder-blocks-algorithm=simple \
+|| tryflag CFLAGS_AUTO -fno-reorder-blocks
+tryflag CFLAGS_AUTO -fno-prefetch-loop-arrays
+tryflag CFLAGS_AUTO -fno-tree-ch
+fi
 test "$optimize" = yes && optimize="internal,malloc,string"
 
 if fnmatch 'no|size' "$optimize" ; then :
@@ -671,9 +692,7 @@ trycppif __mips_soft_float "$t" && SUBARCH=${SUBARCH}-sf
 fi
 
 if test "$ARCH" = "powerpc" ; then
-trycppif "__NO_FPRS__ && !_SOFT_FLOAT" "$t" && fail \
-  "$0: error: compiler's floating point configuration is unsupported"
-trycppif _SOFT_FLOAT "$t" && SUBARCH=${SUBARCH}-sf
+trycppif "_SOFT_FLOAT || __NO_FPRS__" "$t" && SUBARCH=${SUBARCH}-sf
 printf "checking whether compiler can use 'd' constraint in asm... "
 echo 'double f(double x) { __asm__ ("fabs %0, %1" : "=d"(x) : "d"(x)); return x; }' > "$tmpc"
 if $CC $CFLAGS_C99FSE $CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
@@ -725,11 +744,6 @@ fi
 test "$SUBARCH" \
 && printf "configured for %s variant: %s\n" "$ARCH" "$ARCH$SUBARCH"
 
-case "$ARCH$SUBARCH" in
-arm) ASMSUBARCH=el ;;
-*) ASMSUBARCH=$SUBARCH ;;
-esac
-
 #
 # Some archs (powerpc) have different possible long double formats
 # that the compiler can be configured for. The logic for whether this