Bruno Haible <br...@clisp.org> writes:
>> As you can see, this defines an inline version of strtod() that
>> conflicts with the out-of-line version in lib/strtod.c.
>>
>> Is there an idiomatic solution for this kind of problem?
>
> Why does it conflict? gnulib's <stdlib.h> replacement already contains the
> idiomatic solution. As you can see from m4/strtod.m4, there are three cases:
Oops. You are right, of course.
The problem is that AC_FUNC_STRTOD assumes that strtod does not
exist when cross-compiling, which in turn makes the strtod module
assume that it does not need to handle an existing declaration.
Here is a much better (and shorter) version. Comments?
Thanks,
Ben.
--8<--------------------------cut here-------------------------->8--
>From 7765828c11c214d2d6de33b6b87ba2e94da2bc99 Mon Sep 17 00:00:00 2001
From: Ben Pfaff <b...@cs.stanford.edu>
Date: Sun, 13 Jun 2010 15:13:48 -0700
Subject: [PATCH] Properly check for strtod() when cross-compiling.
* m4/strtod.m4: When cross-compiling, do not assume that no strtod()
implementation exists. Check, and then replace the existing implementation
if there is one. Fixes a problem with strtod() when cross-compiling to
Mingw.
---
ChangeLog | 8 ++++++++
m4/strtod.m4 | 20 ++++++++++++++------
2 files changed, 22 insertions(+), 6 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index 8e057f7..2c4db7c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2010-06-10 Ben Pfaff <b...@cs.stanford.edu>
+
+ Properly check for strtod() when cross-compiling.
+ * m4/strtod.m4: When cross-compiling, do not assume that no
+ strtod() implementation exists. Check, and then replace the
+ existing implementation if there is one. Fixes a problem with
+ strtod() when cross-compiling to Mingw.
+
2010-06-09 Ben Pfaff <b...@cs.stanford.edu>
Provide means to uninstall ".bin" files installed by relocwrapper.
diff --git a/m4/strtod.m4 b/m4/strtod.m4
index 4cccb6d..f5977f4 100644
--- a/m4/strtod.m4
+++ b/m4/strtod.m4
@@ -1,4 +1,4 @@
-# strtod.m4 serial 14
+# strtod.m4 serial 15
dnl Copyright (C) 2002-2003, 2006-2010 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
@@ -11,7 +11,13 @@ AC_DEFUN([gl_FUNC_STRTOD],
dnl Note: AC_FUNC_STRTOD does AC_LIBOBJ([strtod]).
if test $ac_cv_func_strtod = no; then
HAVE_STRTOD=0
- gl_PREREQ_STRTOD
+
+ # AC_FUNC_STRTOD assumes that strtod is missing when cross-compiling,
+ # but to reliably provide it we need to know whether it is declared.
+ AC_CHECK_DECLS_ONCE([strtod])
+ if test "$ac_cv_have_decl_strtod" = yes; then
+ REPLACE_STRTOD=1
+ fi
else
AC_CACHE_CHECK([whether strtod obeys C99], [gl_cv_func_strtod_works],
[AC_RUN_IFELSE([AC_LANG_PROGRAM([[
@@ -77,10 +83,12 @@ numeric_equal (double x, double y)
[gl_cv_func_strtod_works="guessing no"])])
if test "$gl_cv_func_strtod_works" != yes; then
REPLACE_STRTOD=1
- gl_PREREQ_STRTOD
- dnl Use undocumented macro to set POW_LIB correctly.
- _AC_LIBOBJ_STRTOD
- fi
+ fi
+ fi
+ if test $HAVE_STRTOD = 0 || test $REPLACE_STRTOD = 1; then
+ gl_PREREQ_STRTOD
+ dnl Use undocumented macro to set POW_LIB correctly.
+ _AC_LIBOBJ_STRTOD
fi
])
--
1.7.1
--
"It was then I realized how dire my medical situation was. Here I was,
a network admin, unable to leave, and here was someone with a broken
network. And they didn't ask me to fix it. They didn't even try to
casually pry a hint out of me." --Ryan Tucker in the Monastery
