Commit b2dcf034 authored by Kamil Dudka's avatar Kamil Dudka
Browse files

curl-compilers.m4: improve detection of GCC's -fvisibility= flag 

Some builds of GCC produce output on both stdout and stderr when --help
--verbose is used.  The 2>&1 redirection caused them to be arbitrarily
interleaved with each other because of stream buffering.  Consequently,
grep failed to match the fvisibility= string in the mixed output, even
though the string was present in GCC's standard output.

This led to silently disabling symbol hiding in some builds of curl.
parent 5f2e3b88

RELEASE-NOTES

+1 −0
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@ This release includes the following bugfixes: 
 o http: Fix HTTP/2 connection reuse [regression] [12]

 o checksrc: Add LoadLibrary to the banned functions list

 o schannel: Disable ALPN on Windows < 8.1 [13]

 o configure: occasional ignorance of --enable-symbol-hiding with GCC



This release includes the following known bugs:

m4/curl-compilers.m4

+2 −2
Original line number Diff line number Diff line
@@ -21,7 +21,7 @@ 
#***************************************************************************



# File version for 'aclocal' use. Keep it a single number.

# serial 66

# serial 67





dnl CURL_CHECK_COMPILER
@@ -1374,7 +1374,7 @@ AC_DEFUN([CURL_CHECK_COMPILER_SYMBOL_HIDING], [ 
    GNU_C)

      dnl Only gcc 3.4 or later

      if test "$compiler_num" -ge "304"; then

        if $CC --help --verbose 2>&1 | grep fvisibility= > /dev/null ; then

        if $CC --help --verbose 2>/dev/null | grep fvisibility= >/dev/null ; then

          tmp_EXTERN="__attribute__ ((__visibility__ (\"default\")))"

          tmp_CFLAGS="-fvisibility=hidden"

          supports_symbol_hiding="yes"