Re: [Mingw-cross-env-list] Qt 4.7 (help wanted)

[Mark Brand]

> How can we influence that search order? Is it possible to pass
> some corresponding ./configure options to GCC in src/gcc.mk?
>
> How did the Qt people do that? Did they patch GCC to get that
> behaviour? Does the GCC contain some special handling in the
> paths when it is built for mingw? If so, why don't _we_ trigger
> that special handling, too?

This problem has been driving me crazy, and I'm not the only one it 
seems.  I'm sure I don't understand all the issues, but here is a quick 
summary:

-We are in good company. There are many reports in various places about 
this.
-The mingw32 cross RPMs from opensuse have the same "problem" with float.h.
-Undefined symbols _clear87 and _control87 are commons symptoms of this 
problem, especially when building Qt.
-No standard solution as far as I can tell.
-I still don't understand how Qt managed to build GCC 4.4 with the mingw 
include directory first.
-I spent too much time trying without success to build GCC 4.5 with the 
mingw include directory first. ):
-It's probably correct to have the gcc include directory *before* the 
mingw include directory anyway.

The least offensive solution I come up with is to move the 
"#include_next" to the other float.h as in the diff below. How does that 
strike you?


regards,
Mark


diff -r cd3ff105f48e src/gcc.mk
--- a/src/gcc.mk        Mon May 31 16:37:35 2010 +0200
+++ b/src/gcc.mk        Wed Jun 02 11:55:15 2010 +0200
@@ -49,6 +49,8 @@
     $(MAKE) -C '$(1)/build' -j '$(JOBS)'
     $(MAKE) -C '$(1)/build' -j 1 install

+    echo "#include_next<float.h>" >> 
'$(PREFIX)/lib/gcc/$(TARGET)/4.5.0/include/float.h'
+
     # create pkg-config script
     (echo '#!/bin/sh'; \
      echo 'PKG_CONFIG_PATH= 
PKG_CONFIG_LIBDIR='\''$(PREFIX)/$(TARGET)/lib/pkgconfig'\'' exec 
pkg-config --static "$$@"') \
diff -r cd3ff105f48e src/mingwrt.mk
--- a/src/mingwrt.mk    Mon May 31 16:37:35 2010 +0200
+++ b/src/mingwrt.mk    Wed Jun 02 11:55:15 2010 +0200
@@ -22,4 +22,5 @@
     $(INSTALL) -d '$(PREFIX)/$(TARGET)'
     cd '$(1)' && \
         cp -rpv include lib '$(PREFIX)/$(TARGET)'
+    '$(SED)' -i 
's,#include_next<float.h>,/*#include_next<float.h>*/,g;' 
'$(PREFIX)/$(TARGET)/include/float.h'
 endef
diff -r cd3ff105f48e src/qt-1-win32.patch
--- a/src/qt-1-win32.patch      Mon May 31 16:37:35 2010 +0200
+++ b/src/qt-1-win32.patch      Wed Jun 02 11:55:15 2010 +0200
@@ -385,7 +385,7 @@
 +QMAKE_LEXFLAGS                =
 +QMAKE_YACC            = byacc
 +QMAKE_YACCFLAGS               = -d
-+QMAKE_CFLAGS          = -pipe -isystem /usr/i686-pc-mingw32/include
++QMAKE_CFLAGS          = -pipe
 +QMAKE_CFLAGS_DEPS     = -M
 +QMAKE_CFLAGS_WARN_ON  = -Wall
 +QMAKE_CFLAGS_WARN_OFF = -w