[PATCH 13/14] Clobber global CFLAGS etc. when requiring GNU compilers.

[Stefano Lattarini]

Currently, if a test script requires (say) "gcc", it will only get CC, not
CFLAGS, redefined in the environment.  This way, if CFLAGS is set referring
to a non-GNU C compiler, its contents won't necessarly be understood by
gcc, and hence a spurious failure will be triggered.

This has already happened in practice, e.g.:
> > depcomp3.test fails since it requires gcc and the test therefore
> > changes CC from cl to gcc, but that's not enough since I also have
> > CFLAGS=-MD which means something completely different to these two
> > compilers. It seems fundamentally broken to assume that CFLAGS
> > remains sane while changing CC.
> Correct.  Another testsuite issue.
(from a discussion between Peter Rosin and Ralf Wildenhues, see
<http://lists.gnu.org/archive/html/automake-patches/2010-06/msg00112.html>)

This patch aims at fixing it.

Regards,
    Stefano

-*-*-*-

* tests/defs.in (require_compiler): Clobber global compiler flags
variables (e.g. CFLAGS, CXXFLAGS, ...) when requiring a GNU
compiler.  But let the user override them with corresponding
`GNU_*' variables (e.g. GNU_CFLAGS for CFLAGS).
(icc in $required): Similarly, clobber global CFLAGS and redefine
it with with $INTEL_CFLAGS.
* tests/ansi3.test: Do not clobber user CFLAGS, it is no more
necessary.
* tests/ansi3b.test: Likewise.
... (other tests changed likewise) ....

From 735da2119912f94aa88fab5e10d0ef514fe6cc7f Mon Sep 17 00:00:00 2001
From: Stefano Lattarini <address@hidden>
Date: Fri, 2 Jul 2010 12:41:30 +0200
Subject: [PATCH 13/14] Clobber global CFLAGS etc. when requiring GNU compilers.

Before this change, if a test script required (say) "gcc", it would have
only got CC, not CFLAGS, redefined in the environment.  This way, if
CFLAGS was already set referring to a non-GNU C compiler, its contents
would have not necessarly been understood by gcc, hence leading to a
spurious failure.

* tests/defs.in (require_compiler): Clobber global compiler flags
variables (e.g. CFLAGS, CXXFLAGS, ...) when requiring a GNU
compiler.  But let the user override them with corresponding
`GNU_*' variables (e.g. GNU_CFLAGS for CFLAGS).
(icc in $required): Similarly, clobber global CFLAGS and redefine
it with with $INTEL_CFLAGS.
* tests/ansi3.test: Do not clobber user CFLAGS, it is no more
necessary.
* tests/ansi3b.test: Likewise.
* tests/ansi5.test: Likewise.
* tests/ccnoco.test: Likewise.
* tests/ccnoco3.test: Likewise.
* tests/cond16.test: Likewise.
* tests/cond18.test: Likewise.
* tests/cond19.test: Likewise.
* tests/cond4.test: Likewise.
* tests/depcomp2.test: Likewise.
* tests/depend2.test: Likewise.
* tests/lex3.test: Likewise.
* tests/pr87.test: Likewise.
* tests/subobj3.test: Likewise.
* tests/substref.test: Likewise.
---
 ChangeLog           |   24 ++++++++++++++++++++++++
 tests/ansi3.test    |    4 ----
 tests/ansi3b.test   |    4 ----
 tests/ansi5.test    |    4 +---
 tests/ccnoco.test   |    7 +------
 tests/ccnoco3.test  |    7 ++-----
 tests/cond16.test   |    4 ----
 tests/cond18.test   |    4 ----
 tests/cond19.test   |    4 ----
 tests/cond4.test    |    4 ----
 tests/defs.in       |   22 ++++++++++++++++++----
 tests/depcomp2.test |    4 ----
 tests/depend2.test  |    4 ----
 tests/lex3.test     |    4 ----
 tests/pr87.test     |    4 ----
 tests/subobj3.test  |    4 ----
 tests/substref.test |    4 ----
 17 files changed, 46 insertions(+), 66 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 0d1e536..889e85d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,29 @@
 2010-07-02  Stefano Lattarini  <address@hidden>
 
+       Clobber global CFLAGS etc. when requiring GNU compilers.
+       * tests/defs.in (require_compiler): Clobber global compiler flags
+       variables (e.g. CFLAGS, CXXFLAGS, ...) when requiring a GNU
+       compiler.  But let the user override them with corresponding
+       `GNU_*' variables (e.g. GNU_CFLAGS for CFLAGS).
+       (icc in $required): Similarly, clobber global CFLAGS and redefine
+       it with with $INTEL_CFLAGS.
+       * tests/ansi3.test: Do not clobber user CFLAGS, it is no more
+       necessary.
+       * tests/ansi3b.test: Likewise.
+       * tests/ansi5.test: Likewise.
+       * tests/ccnoco.test: Likewise.
+       * tests/ccnoco3.test: Likewise.
+       * tests/cond16.test: Likewise.
+       * tests/cond18.test: Likewise.
+       * tests/cond19.test: Likewise.
+       * tests/cond4.test: Likewise.
+       * tests/depcomp2.test: Likewise.
+       * tests/depend2.test: Likewise.
+       * tests/lex3.test: Likewise.
+       * tests/pr87.test: Likewise.
+       * tests/subobj3.test: Likewise.
+       * tests/substref.test: Likewise.
+
        Refactor code requiring compilers in testsuite.
        * tests/defs.in (require_gnu_compilers): Removed, merged ...
        (require_compiler): ... with this one, and added knowledge of
diff --git a/tests/ansi3.test b/tests/ansi3.test
index e1e0c42..2bff0e5 100755
--- a/tests/ansi3.test
+++ b/tests/ansi3.test
@@ -44,10 +44,6 @@ main (int argc, char *argv[])
 }
 END
 
-# Ignore user CFLAGS.
-CFLAGS=
-export CFLAGS
-
 # We use gcc and not gcc -traditional as the latter fails on some
 # Linux boxes (Red Hat 5.1 in particular).
 $ACLOCAL
diff --git a/tests/ansi3b.test b/tests/ansi3b.test
index ad222ff..8b50b29 100755
--- a/tests/ansi3b.test
+++ b/tests/ansi3b.test
@@ -45,10 +45,6 @@ main (int argc, char *argv[])
 }
 END
 
-# Ignore user CFLAGS.
-CFLAGS=
-export CFLAGS
-
 # We use gcc and not gcc -traditional as the latter fails on some
 # Linux boxes (Red Hat 5.1 in particular).
 $ACLOCAL
diff --git a/tests/ansi5.test b/tests/ansi5.test
index bbc9109..f607a0c 100755
--- a/tests/ansi5.test
+++ b/tests/ansi5.test
@@ -68,9 +68,7 @@ set -e
 $ACLOCAL
 $AUTOCONF
 $AUTOMAKE -a
-# Ignore user CFLAGS.
-CFLAGS=
-export CFLAGS
+
 ./configure
 
 # This is ugly!  If we set U at make time then the "wrong" file gets
diff --git a/tests/ccnoco.test b/tests/ccnoco.test
index d6ed136..a455d89 100755
--- a/tests/ccnoco.test
+++ b/tests/ccnoco.test
@@ -1,5 +1,5 @@
 #! /bin/sh
-# Copyright (C) 2001, 2002, 2008  Free Software Foundation, Inc.
+# Copyright (C) 2001, 2002, 2008, 2010 Free Software Foundation, Inc.
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -70,11 +70,6 @@ chmod +x Mycomp
 
 set -e
 
-
-# Ignore user CFLAGS.
-CFLAGS=
-export CFLAGS
-
 for conf in configure.1 configure.3; do
    cp $conf configure.in
 
diff --git a/tests/ccnoco3.test b/tests/ccnoco3.test
index 2e9cd37..0b27c09 100755
--- a/tests/ccnoco3.test
+++ b/tests/ccnoco3.test
@@ -1,5 +1,6 @@
 #! /bin/sh
-# Copyright (C) 2001, 2002, 2008, 2009  Free Software Foundation, Inc.
+# Copyright (C) 2001, 2002, 2008, 2009, 2010 Free Software Foundation,
+# Inc.
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -58,10 +59,6 @@ END
 
 chmod +x Mycomp
 
-# Ignore user CFLAGS.
-CFLAGS=
-export CFLAGS
-
 $ACLOCAL
 $AUTOCONF
 $AUTOMAKE --copy --add-missing
diff --git a/tests/cond16.test b/tests/cond16.test
index 950ab10..f333f43 100755
--- a/tests/cond16.test
+++ b/tests/cond16.test
@@ -48,10 +48,6 @@ echorule:
 
 END
 
-# Ignore user CFLAGS.
-CFLAGS=
-export CFLAGS
-
 set -e
 
 $ACLOCAL
diff --git a/tests/cond18.test b/tests/cond18.test
index 312b896..81cc3bb 100755
--- a/tests/cond18.test
+++ b/tests/cond18.test
@@ -53,10 +53,6 @@ echorule:
 bin_PROGRAMS = helldl
 END
 
-# Ignore user CFLAGS.
-CFLAGS=
-export CFLAGS
-
 set -e
 
 $ACLOCAL
diff --git a/tests/cond19.test b/tests/cond19.test
index d820202..eced6f6 100755
--- a/tests/cond19.test
+++ b/tests/cond19.test
@@ -55,10 +55,6 @@ echorule:
 bin_PROGRAMS = helldl
 END
 
-# Ignore user CFLAGS.
-CFLAGS=
-export CFLAGS
-
 set -e
 
 $ACLOCAL
diff --git a/tests/cond4.test b/tests/cond4.test
index 1d2910c..223f91f 100755
--- a/tests/cond4.test
+++ b/tests/cond4.test
@@ -53,10 +53,6 @@ test "`grep 'address@hidden@' Makefile.in | wc -l`" -eq 0
 
 $AUTOCONF
 
-# Ignore user CFLAGS.
-CFLAGS=
-export CFLAGS
-
 CONDITION1=true CONDITION2=true ./configure
 msgtt=`$MAKE --no-print-directory echo-objects`
 CONDITION1=true CONDITION2=false ./configure
diff --git a/tests/defs.in b/tests/defs.in
index d34d425..89c06da 100644
--- a/tests/defs.in
+++ b/tests/defs.in
@@ -102,19 +102,24 @@ require_compiler()
   case $1 in
     c)
       compiler_variable=CC
+      flags_variable=CFLAGS # FIXME: what about CPPFLAGS?
       gnu_compiler_candidates=gcc;;
     c++)
       compiler_variable=CXX
+      flags_variable=CXXFLAGS # FIXME: what about CPPFLAGS?
       gnu_compiler_candidates=g++;;
     f77)
       compiler_variable=F77
+      flags_variable=FFLAGS
       # gfortran should be able to seamlessly compile Fortran 77 code
       gnu_compiler_candidates='g77 gfortran';;
     f9x)
       compiler_variable=FC
+      flags_variable=FCLAGS
       gnu_compiler_candidates=gfortran;;
     gcj)
       compiler_variable=GCJ
+      flags_variable='' # flags must be GNU-specific anyway
       gnu_compiler_candidates=gcj;;
     *)
       echo "$me: $1: invalid compiler language" >&2; exit 99;;
@@ -148,10 +153,18 @@ require_compiler()
     $have_gnu_compiler || exit 77
     eval "$compiler_variable=\$compiler"
     export $compiler_variable
+    if test x"$what_gnu" = x"force" && test -n "$flags_variable"; then
+      # Clobber compiler flags in the environment, so that they won't be
+      # passed to the GNU compiler; however, leave the user a way to
+      # specify flags for the GNU compiler, by using e.g. GNU_CFLAGS
+      # instead of CFLAGS, etcetera.
+      eval "$flags_variable=\$GNU_$flags_variable"
+      export $flags_variable
+    fi
   fi
  
   # Remove local variables.
-  unset what_gnu compiler_variable compiler
+  unset what_gnu compiler_variable compiler flags_variables
   unset gnu_compiler_candidates have_gnu_compiler
 }
 
@@ -214,12 +227,13 @@ do
       # required.
       case " $required " in
         *\ fortran77\ *);;
-        *) F77=$FC; export F77;;
+        # Hmpf.  Some code duplication here w.r.t. require_compiler().
+        *) F77=$FC; export F77; FFLAGS=${GNU_FFLAGS-}; export FFLAGS;;
       esac
       ;;
     icc)
-      CC=icc
-      export CC
+      CC=icc; export CC
+      CFLAGS=${INTEL_CFLAGS-}; export CFLAGS
       # There is no way to ask *only* the compiler's version.
       # This tool always wants to do something (by default
       # it will try link *nothing* and complain it cannot find
diff --git a/tests/depcomp2.test b/tests/depcomp2.test
index 2dca558..5b3ccc3 100755
--- a/tests/depcomp2.test
+++ b/tests/depcomp2.test
@@ -42,10 +42,6 @@ END
 
 : > subdir/foo.c
 
-# Ignore user CFLAGS.
-CFLAGS=
-export CFLAGS
-
 $ACLOCAL
 $AUTOMAKE --add-missing
 $AUTOCONF
diff --git a/tests/depend2.test b/tests/depend2.test
index 114664d..f14450f 100755
--- a/tests/depend2.test
+++ b/tests/depend2.test
@@ -51,10 +51,6 @@ $ACLOCAL
 $AUTOCONF
 $AUTOMAKE -a
 
-# Ignore user CFLAGS.
-CFLAGS=
-export CFLAGS
-
 ./configure --disable-dependency-tracking
 
 $MAKE
diff --git a/tests/lex3.test b/tests/lex3.test
index 6e5241b..c026d10 100755
--- a/tests/lex3.test
+++ b/tests/lex3.test
@@ -21,10 +21,6 @@
 required='cc gzip flex GNUmake'
 . ./defs || Exit 1
 
-# Ignore user CFLAGS.
-CFLAGS=
-export CFLAGS
-
 cat > configure.in << 'END'
 AC_INIT
 dnl Prevent automake from looking in .. and ../..
diff --git a/tests/pr87.test b/tests/pr87.test
index 634ca20..3e715a6 100755
--- a/tests/pr87.test
+++ b/tests/pr87.test
@@ -41,10 +41,6 @@ AC_PROG_CC
 AC_OUTPUT(Makefile `echo $subdirs | sed 's|\([a-z][a-z]*\)|\1/Makefile|g'`)
 EOF
 
-# Ignore user CFLAGS.
-CFLAGS=
-export CFLAGS
-
 touch README NEWS AUTHORS ChangeLog
 
 mkdir build
diff --git a/tests/subobj3.test b/tests/subobj3.test
index a21c6a0..ff14c4e 100755
--- a/tests/subobj3.test
+++ b/tests/subobj3.test
@@ -51,10 +51,6 @@ main (int argc, char *argv[])
 }
 END
 
-# Ignore user CFLAGS.
-CFLAGS=
-export CFLAGS
-
 $ACLOCAL
 $AUTOCONF
 $AUTOMAKE -a
diff --git a/tests/substref.test b/tests/substref.test
index adc3c5c..8471c4f 100755
--- a/tests/substref.test
+++ b/tests/substref.test
@@ -46,10 +46,6 @@ got:
 
 END
 
-# Ignore user CFLAGS.
-CFLAGS=
-export CFLAGS
-
 $ACLOCAL
 $AUTOCONF
 $AUTOMAKE -a
-- 
1.6.5