0006-PR-build-21187-Static-linking-of-libstdc-and-libgcc-.patch

From 6cd50b7d67ebc00af0740dde69c69d7056154c80 Mon Sep 17 00:00:00 2001
From: Nitish K Mishra <nitismis@in.ibm.com>
Date: Thu, 12 Oct 2017 14:20:31 +0100
Subject: [PATCH 6/6] [PR build/21187] Static linking of libstdc++ and libgcc
 with GDB leads to broken exception handling on AIX platform

See https://sourceware.org/bugzilla/show_bug.cgi?id=21187
See also https://sourceware.org/ml/gdb/2017-01/msg00044.html et seq.

As pointed out in that thread, this is papering over the cracks: We don't
seem to know why exceptions aren't being propagated correctly, or why using
a shared library fixes it.

(Doing that also prevents building a standlone GDB binary for Windows (which
can be easily distributed)

Other solutions suggested therein: build x86 readline with -fexceptions?

This problem also affects MinGW and Cygwin x86.
See also https://sourceware.org/bugzilla/show_bug.cgi?id=21078

ChangeLog:

2016-03-01  Nitish K Mishra  <nitismis@in.ibm.com>

        * configure.ac: Include one more option "--disable-staticlib"
        to link libstdc++ and libgcc dynamically.
---
 ChangeLog    |  5 +++++
 configure    | 26 +++++++++++++++++++++++---
 configure.ac | 21 ++++++++++++++++++---
 3 files changed, 46 insertions(+), 6 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index bfe7adf0ae..8c73b1d0e3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2016-03-01  Nitish K Mishra  <nitismis@in.ibm.com>
+
+        * configure.ac: Include one more option "--disable-staticlib"
+        to link libstdc++ and libgcc dynamically.
+
 2017-01-01  Joel Brobecker  <brobecker@adacore.com>
 
         Update copyright year range in all GDB files.
diff --git a/configure b/configure
index a5f4fc5aa7..6f57d5c041 100755
--- a/configure
+++ b/configure
@@ -760,6 +760,7 @@ enable_libquadmath_support
 enable_libada
 enable_libssp
 enable_libstdcxx
+enable_staticlib
 enable_liboffloadmic
 enable_static_libjava
 enable_bootstrap
@@ -1487,6 +1488,8 @@ Optional Features:
   --enable-libada         build libada directory
   --enable-libssp         build libssp directory
   --disable-libstdcxx     do not build libstdc++-v3 directory
+  --disable-staticlib     do not link libstdc++ and libgcc library statically,
+                          default is static linking
   --enable-liboffloadmic=ARG
                           build liboffloadmic [ARG={no,host,target}]
   --enable-static-libjava[=ARG]
@@ -3110,6 +3113,15 @@ if test "${ENABLE_LIBSTDCXX}" = "no" ; then
   noconfigdirs="$noconfigdirs target-libstdc++-v3"
 fi
 
+# Check whether --enable-staticlib was given.
+if test "${enable_staticlib+set}" = set; then :
+  enableval=$enable_staticlib; ENABLE_STATICLIB=$enableval
+else
+  ENABLE_STATICLIB=yes
+fi
+
+
+
 # If this is accelerator compiler and its target is intelmic we enable
 # target liboffloadmic by default.  If this is compiler with offloading
 # for intelmic we enable host liboffloadmic by default.  Otherwise
@@ -5109,9 +5121,10 @@ if test -z "$LD"; then
   fi
 fi
 
-# Check whether -static-libstdc++ -static-libgcc is supported.
+# If ENABLE_STATICLIB is set for configuration, check whether -static-libstdc++ -static-libgcc is supported
 have_static_libs=no
-if test "$GCC" = yes; then
+if test "$ENABLE_STATICLIB" = yes; then
+ if test "$GCC" = yes; then
   saved_LDFLAGS="$LDFLAGS"
 
   LDFLAGS="$LDFLAGS -static-libstdc++ -static-libgcc"
@@ -5149,6 +5162,7 @@ ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
 
   LDFLAGS="$saved_LDFLAGS"
+ fi
 fi
 
 
@@ -5903,6 +5917,9 @@ else
  # trust that they are doing what they want.
  if test "$stage1_libs" = "" -a "$have_static_libs" = yes; then
    stage1_ldflags="-static-libstdc++ -static-libgcc"
+   else
+  # If static lib is disabled.
+   stage1_ldflags=""
  fi
 fi
 
@@ -5937,8 +5954,11 @@ else
  # In stages 2 and 3, default to linking libstdc++ and libgcc
  # statically.  But if the user explicitly specified the libraries to
  # use, trust that they are doing what they want.
- if test "$poststage1_libs" = ""; then
+ if test "$poststage1_libs" = "" -a "$have_static_libs" = yes; then
    poststage1_ldflags="-static-libstdc++ -static-libgcc"
+   else
+   # If static library linking is disabled.
+   poststage1_ldflags=""
  fi
 fi
 
diff --git a/configure.ac b/configure.ac
index a27985c0a7..e90b8e166e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -471,6 +471,13 @@ ENABLE_LIBSTDCXX=default)
   noconfigdirs="$noconfigdirs target-libstdc++-v3"
 fi]
 
+AC_ARG_ENABLE(staticlib,
+AS_HELP_STRING([--disable-staticlib],
+  [do not link libstdc++ and libgcc library statically, default is static linking]),
+ENABLE_STATICLIB=$enableval,
+ENABLE_STATICLIB=yes)
+
+
 # If this is accelerator compiler and its target is intelmic we enable
 # target liboffloadmic by default.  If this is compiler with offloading
 # for intelmic we enable host liboffloadmic by default.  Otherwise
@@ -1406,9 +1413,10 @@ if test -z "$LD"; then
   fi
 fi
 
-# Check whether -static-libstdc++ -static-libgcc is supported.
+# If ENABLE_STATICLIB is set for configuration, check whether -static-libstdc++ -static-libgcc is supported
 have_static_libs=no
-if test "$GCC" = yes; then
+if test "$ENABLE_STATICLIB" = yes; then
+ if test "$GCC" = yes; then
   saved_LDFLAGS="$LDFLAGS"
 
   LDFLAGS="$LDFLAGS -static-libstdc++ -static-libgcc"
@@ -1424,6 +1432,7 @@ int main() {}],
   AC_LANG_POP(C++)
 
   LDFLAGS="$saved_LDFLAGS"
+ fi
 fi
 
 ACX_PROG_GNAT
@@ -1741,6 +1750,9 @@ AC_ARG_WITH(stage1-ldflags,
  # trust that they are doing what they want.
  if test "$stage1_libs" = "" -a "$have_static_libs" = yes; then
    stage1_ldflags="-static-libstdc++ -static-libgcc"
+   else
+  # If static lib is disabled.
+   stage1_ldflags=""
  fi])
 AC_SUBST(stage1_ldflags)
 
@@ -1768,8 +1780,11 @@ AC_ARG_WITH(boot-ldflags,
  # In stages 2 and 3, default to linking libstdc++ and libgcc
  # statically.  But if the user explicitly specified the libraries to
  # use, trust that they are doing what they want.
- if test "$poststage1_libs" = ""; then
+ if test "$poststage1_libs" = "" -a "$have_static_libs" = yes; then
    poststage1_ldflags="-static-libstdc++ -static-libgcc"
+   else
+   # If static library linking is disabled.
+   poststage1_ldflags=""
  fi])
 AC_SUBST(poststage1_ldflags)
 
-- 
2.14.2