[PATCH] Riscv shared libraries should not export __global_pointer$.
Jim Wilson
jimw@sifive.com
Tue Dec 5 01:38:00 GMT 2017
This fixes issue #108 in the riscv-binutils-gdb project on github.
https://github.com/riscv/riscv-binutils-gdb/issues/108
The problem here is that the riscv linker is exporting __global_pointer$ which
is wrong. This symbol serves the same function as the mips _gp. It is set by
the linker script in every executable/shared library and should not be
exported. Exporting it can lead to linker errors as reported in #108. The
fix is use HIDDEN for __global_pointer$, same as the mips port uses HIDDEN
for _gp.
The mips port has some nice testcases for this, so I borrowed them to use
for the riscv target. I also noticed that the riscv specific linker tests
weren't being run because of a typo in the target check. This is fixed by
this patch also.
This was tested with check-binutils/check-gas/check-ld on riscv32 and riscv64.
There were no regressions. Committed.
ld/
* emulparams/elf32lriscv-defs.sh (SDATA_START_SYMBOLS): Mark
__global_pointer$ as HIDDEN.
* testsuite/ld-riscv-elf/gp-hidden-64.rd: New.
* testsuite/ld-riscv-elf/gp-hidden-lib.rd: New.
* testsuite/ld-riscv-elf/gp-hidden-lib.s: New.
* testsuite/ld-riscv-elf/gp-hidden-ver-64.rd: New.
* testsuite/ld-riscv-elf/gp-hidden-ver.rd: New.
* testsuite/ld-riscv-elf/gp-hidden-ver.s: New.
* testsuite/ld-riscv-elf/gp-hidder-ver.ver: New.
* testsuite/ld-riscv-elf/gp-hidden.rd: New.
* testsuite/ld-riscv-elf/gp-hidden.s: New.
* testsuite/ld-riscv-elf/gp-hidden.sd: New.
* testsuite/ld-riscv-elf/ld-riscv-elf.exp: Change riscv to riscv*.
Run the new tests with run_ld_link_tests.
---
ld/emulparams/elf32lriscv-defs.sh | 2 +-
ld/testsuite/ld-riscv-elf/gp-hidden-64.rd | 4 ++++
ld/testsuite/ld-riscv-elf/gp-hidden-lib.rd | 5 ++++
ld/testsuite/ld-riscv-elf/gp-hidden-lib.s | 6 +++++
ld/testsuite/ld-riscv-elf/gp-hidden-ver-64.rd | 6 +++++
ld/testsuite/ld-riscv-elf/gp-hidden-ver.rd | 6 +++++
ld/testsuite/ld-riscv-elf/gp-hidden-ver.s | 7 ++++++
ld/testsuite/ld-riscv-elf/gp-hidden-ver.ver | 1 +
ld/testsuite/ld-riscv-elf/gp-hidden.rd | 4 ++++
ld/testsuite/ld-riscv-elf/gp-hidden.s | 7 ++++++
ld/testsuite/ld-riscv-elf/gp-hidden.sd | 9 +++++++
ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp | 34 ++++++++++++++++++++++++++-
12 files changed, 89 insertions(+), 2 deletions(-)
create mode 100644 ld/testsuite/ld-riscv-elf/gp-hidden-64.rd
create mode 100644 ld/testsuite/ld-riscv-elf/gp-hidden-lib.rd
create mode 100644 ld/testsuite/ld-riscv-elf/gp-hidden-lib.s
create mode 100644 ld/testsuite/ld-riscv-elf/gp-hidden-ver-64.rd
create mode 100644 ld/testsuite/ld-riscv-elf/gp-hidden-ver.rd
create mode 100644 ld/testsuite/ld-riscv-elf/gp-hidden-ver.s
create mode 100644 ld/testsuite/ld-riscv-elf/gp-hidden-ver.ver
create mode 100644 ld/testsuite/ld-riscv-elf/gp-hidden.rd
create mode 100644 ld/testsuite/ld-riscv-elf/gp-hidden.s
create mode 100644 ld/testsuite/ld-riscv-elf/gp-hidden.sd
diff --git a/ld/emulparams/elf32lriscv-defs.sh b/ld/emulparams/elf32lriscv-defs.sh
index ab80333289..5b41d5cd02 100644
--- a/ld/emulparams/elf32lriscv-defs.sh
+++ b/ld/emulparams/elf32lriscv-defs.sh
@@ -23,7 +23,7 @@ TEXT_START_ADDR=0x10000
MAXPAGESIZE="CONSTANT (MAXPAGESIZE)"
COMMONPAGESIZE="CONSTANT (COMMONPAGESIZE)"
-SDATA_START_SYMBOLS="__global_pointer$ = . + 0x800;
+SDATA_START_SYMBOLS="HIDDEN (__global_pointer$ = . + 0x800);
*(.srodata.cst16) *(.srodata.cst8) *(.srodata.cst4) *(.srodata.cst2) *(.srodata .srodata.*)"
INITIAL_READONLY_SECTIONS=".interp : { *(.interp) } ${CREATE_PIE-${INITIAL_READONLY_SECTIONS}}"
diff --git a/ld/testsuite/ld-riscv-elf/gp-hidden-64.rd b/ld/testsuite/ld-riscv-elf/gp-hidden-64.rd
new file mode 100644
index 0000000000..aaaec93d8e
--- /dev/null
+++ b/ld/testsuite/ld-riscv-elf/gp-hidden-64.rd
@@ -0,0 +1,4 @@
+
+Relocation section '\.rela\.dyn' at offset .* contains 1 entry:
+ *Offset * Info * Type * Sym\. *Value * Sym\. *Name \+ Addend
+[0-9a-f]+ * [0-9a-f]+02 * R_RISCV_64 * [0-9a-f]+ * foo \+ 0
diff --git a/ld/testsuite/ld-riscv-elf/gp-hidden-lib.rd b/ld/testsuite/ld-riscv-elf/gp-hidden-lib.rd
new file mode 100644
index 0000000000..59b4442190
--- /dev/null
+++ b/ld/testsuite/ld-riscv-elf/gp-hidden-lib.rd
@@ -0,0 +1,5 @@
+
+Relocation section '\.rela\.dyn' at offset .* contains 1 entry:
+ *Offset * Info * Type * Sym\. *Value * Sym\. *Name \+ Addend
+# This must be an absolute relocation, there must not be a _gp reference.
+[0-9a-f]+ * 0+03 * R_RISCV_RELATIVE * [0-9a-f]+
diff --git a/ld/testsuite/ld-riscv-elf/gp-hidden-lib.s b/ld/testsuite/ld-riscv-elf/gp-hidden-lib.s
new file mode 100644
index 0000000000..04f0655857
--- /dev/null
+++ b/ld/testsuite/ld-riscv-elf/gp-hidden-lib.s
@@ -0,0 +1,6 @@
+ .data
+ .globl bar
+ .type bar, @object
+bar:
+ .dc.a __global_pointer$
+ .size bar, . - bar
diff --git a/ld/testsuite/ld-riscv-elf/gp-hidden-ver-64.rd b/ld/testsuite/ld-riscv-elf/gp-hidden-ver-64.rd
new file mode 100644
index 0000000000..57cb13fc4a
--- /dev/null
+++ b/ld/testsuite/ld-riscv-elf/gp-hidden-ver-64.rd
@@ -0,0 +1,6 @@
+
+Relocation section '\.rela\.dyn' at offset .* contains 2 entries:
+ *Offset * Info * Type * Sym\. *Value * Sym\. *Name \+ Addend
+# This must be an absolute relocation, there must not be a _gp reference.
+[0-9a-f]+ * 0+03 * R_RISCV_RELATIVE * [0-9a-f]+
+[0-9a-f]+ * [0-9a-f]+02 * R_RISCV_64 * [0-9a-f]+ * bar \+ 0
diff --git a/ld/testsuite/ld-riscv-elf/gp-hidden-ver.rd b/ld/testsuite/ld-riscv-elf/gp-hidden-ver.rd
new file mode 100644
index 0000000000..dbed24f81e
--- /dev/null
+++ b/ld/testsuite/ld-riscv-elf/gp-hidden-ver.rd
@@ -0,0 +1,6 @@
+
+Relocation section '\.rela\.dyn' at offset .* contains 2 entries:
+ *Offset * Info * Type * Sym\. *Value * Sym\. *Name \+ Addend
+# This must be an absolute relocation, there must not be a _gp reference.
+[0-9a-f]+ * 0+03 * R_RISCV_RELATIVE * [0-9a-f]+
+[0-9a-f]+ * [0-9a-f]+01 * R_RISCV_32 * [0-9a-f]+ * bar \+ 0
diff --git a/ld/testsuite/ld-riscv-elf/gp-hidden-ver.s b/ld/testsuite/ld-riscv-elf/gp-hidden-ver.s
new file mode 100644
index 0000000000..a197bacd9b
--- /dev/null
+++ b/ld/testsuite/ld-riscv-elf/gp-hidden-ver.s
@@ -0,0 +1,7 @@
+ .data
+ .globl foo
+ .type foo, @object
+foo:
+ .dc.a bar
+ .dc.a __global_pointer$
+ .size foo, . - foo
diff --git a/ld/testsuite/ld-riscv-elf/gp-hidden-ver.ver b/ld/testsuite/ld-riscv-elf/gp-hidden-ver.ver
new file mode 100644
index 0000000000..b6b2365188
--- /dev/null
+++ b/ld/testsuite/ld-riscv-elf/gp-hidden-ver.ver
@@ -0,0 +1 @@
+{ global: foo; local: *; };
diff --git a/ld/testsuite/ld-riscv-elf/gp-hidden.rd b/ld/testsuite/ld-riscv-elf/gp-hidden.rd
new file mode 100644
index 0000000000..dc29f7d058
--- /dev/null
+++ b/ld/testsuite/ld-riscv-elf/gp-hidden.rd
@@ -0,0 +1,4 @@
+
+Relocation section '\.rela\.dyn' at offset .* contains 1 entry:
+ *Offset * Info * Type * Sym\. *Value * Sym\. *Name \+ Addend
+[0-9a-f]+ * [0-9a-f]+01 * R_RISCV_32 * [0-9a-f]+ * foo \+ 0
diff --git a/ld/testsuite/ld-riscv-elf/gp-hidden.s b/ld/testsuite/ld-riscv-elf/gp-hidden.s
new file mode 100644
index 0000000000..18d3ca3d98
--- /dev/null
+++ b/ld/testsuite/ld-riscv-elf/gp-hidden.s
@@ -0,0 +1,7 @@
+ .data
+ .globl blah
+ .type blah, @object
+blah:
+ .dc.a foo
+ .dc.a __global_pointer$
+ .size blah, . - blah
diff --git a/ld/testsuite/ld-riscv-elf/gp-hidden.sd b/ld/testsuite/ld-riscv-elf/gp-hidden.sd
new file mode 100644
index 0000000000..f4321c2b1f
--- /dev/null
+++ b/ld/testsuite/ld-riscv-elf/gp-hidden.sd
@@ -0,0 +1,9 @@
+
+Symbol table '.dynsym' contains [0-9]+ entries:
+ * Num: * Value * Size * Type * Bind * Vis * Ndx * Name
+#...
+Symbol table '.symtab' contains [0-9]+ entries:
+ * Num: * Value * Size * Type * Bind * Vis * Ndx * Name
+#...
+ * [0-9a-f]+: * [0-9a-f]+ * 0 * NOTYPE * LOCAL * DEFAULT .* __global_pointer\$
+#pass
diff --git a/ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp b/ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp
index c219b18159..9f5959cc3b 100644
--- a/ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp
+++ b/ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp
@@ -19,6 +19,38 @@
# MA 02110-1301, USA.
#
-if [istarget "riscv-*-*"] {
+if [istarget "riscv*-*-*"] {
run_dump_test "c-lui"
+
+ set abis { rv32gc ilp32 elf32lriscv rv64gc lp64 elf64lriscv }
+ foreach { arch abi emul } $abis {
+ # This checks whether our linker scripts get the scope of
+ # __global_pointer$ right, and thus must therefore use default scripts.
+ set suff64 [string map {ilp32 "" lp64 -64} $abi]
+ run_ld_link_tests [list \
+ [list "gp scope test ($abi shared library)" \
+ "-m$emul -shared" "" \
+ "-march=$arch -mabi=$abi -fpic" \
+ { gp-hidden-lib.s } \
+ [list \
+ "readelf --relocs gp-hidden-lib.rd" \
+ "readelf --syms gp-hidden.sd"] \
+ "gp-hidden-lib-${abi}.so"] \
+ [list "gp scope test ($abi versioned lib)" \
+ "-m$emul -shared -version-script gp-hidden-ver.ver tmpdir/gp-hidden-lib-${abi}.so" "" \
+ "-march=$arch -mabi=$abi -fpic" \
+ { gp-hidden-ver.s } \
+ [list \
+ "readelf --relocs gp-hidden-ver${suff64}.rd" \
+ "readelf --syms gp-hidden.sd"] \
+ "gp-hidden-ver-${abi}.so"] \
+ [list "gp scope test ($abi executable)" \
+ "-m$emul -e 0 -rpath-link . tmpdir/gp-hidden-ver-${abi}.so" "" \
+ "-march=$arch -mabi=$abi" \
+ {gp-hidden.s} \
+ [list \
+ "readelf --relocs gp-hidden${suff64}.rd" \
+ "readelf --syms gp-hidden.sd"]\
+ "gp-hidden-${abi}"]]
+ }
}
--
2.14.1
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