commit e3621dca154207c1df41123a94b4691f95185adf
author Nicolas Capens <capn@google.com> Tue Feb 25 22:45:42 2020 -0500
committer Nicolas Capens <nicolascapens@google.com> Wed Feb 26 15:51:34 2020 +0000
tree 782ba1c67216f4f070df177b7dcc4e6e03b763ef
parent da659b3741132fe6a6904e45d96112eef776bc28

Build with -Bsymbolic to prevent symbol preemption

The CMake build was already using -fvisibility=protected, which has the
same effect but uses duplicate symbol entries for internal/external use.

Bug: b/148240133
Change-Id: I8069a1b293a6ec0604be32179ed591ffaa645ed7
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/41648
Presubmit-Ready: Nicolas Capens <nicolascapens@google.com>
Tested-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Antonio Maiorano <amaiorano@google.com>

CMakeLists.txt

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1c3a63a..538d360 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -293,8 +293,9 @@
         set_property(TARGET ${TARGET} APPEND_STRING PROPERTY LINK_FLAGS " -Wl,--version-script=${DIR}/${TARGET}.lds")
         set_property(TARGET ${TARGET} APPEND_STRING PROPERTY LINK_DEPENDS "${DIR}/${TARGET}.lds;")
 
-        # Don't allow symbols to be overridden by another module.
-        set_property(TARGET ${TARGET} APPEND_STRING PROPERTY COMPILE_FLAGS " -fvisibility=protected")
+        # -Bsymbolic binds symbol references to their global definitions within
+        # a shared object, thereby preventing symbol preemption.
+        set_property(TARGET ${TARGET} APPEND_STRING PROPERTY COMPILE_FLAGS "  -Wl,-Bsymbolic")
 
         if(ARCH STREQUAL "mipsel" OR ARCH STREQUAL "mips64el")
           # MIPS supports sysv hash-style only.