GENERATE_SHLIB_SCRIPT vs. EMBEDDED
Alan Modra
amodra@gmail.com
Tue Nov 5 04:01:00 GMT 2019
On Tue, Oct 29, 2019 at 10:23:41AM +1030, Alan Modra wrote:
> The error is
> ./ld-new: tmpdir/pr22471: error: PHDR segment not covered by LOAD segment
> which was the case before this patch but ld didn't diagnose the error.
> So not exactly a regression.
>
> In more detail, we have a bunch of targets that have this nastiness in
> their setup: eg. from ld/emulparams/elf32bfin.sh
> GENERATE_SHLIB_SCRIPT=yes
> EMBEDDED=yes
A target that sets EMBEDDED non-empty is one that doesn't want to put
the ELF file header or program header in a memory image. Likely the
target isn't interested in supporting dynamically loaded executables,
shared libraries, or PIEs, because loaders for such binaries generally
require program headers to be present. This isn't 100% true though.
The target might be one where the loader accesses the file system in
order to retrieve headers.
Also, note that not all "shared libraries" require gcc -shared or the
shared library support in the linker. I believe one implementation of
shared libraries on uclinux is like this.
So, this patch removes GENERATE_SHLIB_SCRIPT and GENERATE_PIE_SCRIPT
in most emulparams files where EMBEDDED is set, restoring the shared
lib and pie support in emulparams files that unset EMBEDDED after
including a file where the support is removed.
Exceptions to the general rule that EMBEDDED disables shared libs are:
arm*-*-symbianelf*, where the OS wants shared library support
without ELF program headers in the image, and
sh*-*-uclinux*, where I've left things as they were, ie. both
EMBEDDED and GENERATE_SHLIB_SCRIPT because I'm unsure as to the
shared library scheme.
After this patch the targets I regularly test see these testsuite
changes:
bfin-elf -FAIL: Build pr22471
bfin-elf -FAIL: DT_TEXTREL in shared lib
bfin-elf -FAIL: DT_TEXTREL map file warning
bfin-elf -FAIL: PR ld/21233 dynamic symbols with section GC (--undefined)
bfin-elf -FAIL: PR ld/21233 dynamic symbols with section GC (--require-defined)
bfin-elf -FAIL: PR ld/21233 dynamic symbols with section GC (EXTERN)
bfin-elf -FAIL: Build pr22150
bfin-elf -FAIL: Build pr20995-2.so
bfin-elf -FAIL: undefined symbols in shared lib (dyn reloc)
score-elf -FAIL: Build pr22471
score-elf -FAIL: DT_TEXTREL map file warning
score-elf -FAIL: Build pr22150
score-elf -FAIL: -Bsymbolic-functions
score-elf -FAIL: Build pr20995-2.so
score-elf -FAIL: pr20995
score-elf -FAIL: pr20995-2
sh-rtems -FAIL: Build pr22471
sh-rtems -FAIL: Build pr20995-2.so
sh-rtems -FAIL: pr20995
sh-rtems -FAIL: pr20995-2
* emulparams/aarch64elf.sh (GENERATE_SHLIB_SCRIPT),
(GENERATE_PIE_SCRIPT): Don't set.
* emulparams/aarch64elf32.sh (GENERATE_SHLIB_SCRIPT),
(GENERATE_PIE_SCRIPT): Don't set.
* emulparams/arcelf.sh (GENERATE_SHLIB_SCRIPT): Don't set.
* emulparams/armelf.sh (GENERATE_SHLIB_SCRIPT),
(GENERATE_PIE_SCRIPT): Don't set.
* emulparams/armelf_fbsd.sh (GENERATE_SHLIB_SCRIPT): Set.
* emulparams/armelf_nbsd.sh (GENERATE_SHLIB_SCRIPT),
(GENERATE_PIE_SCRIPT): Set.
* emulparams/armelf_vxworks.sh (GENERATE_SHLIB_SCRIPT): Set.
* emulparams/armsymbian.sh (GENERATE_SHLIB_SCRIPT): Set.
* emulparams/elf32bfin.sh (GENERATE_SHLIB_SCRIPT): Don't set.
* emulparams/elf32microblaze.sh (GENERATE_SHLIB_SCRIPT): Don't set.
* emulparams/score3_elf.sh (GENERATE_SHLIB_SCRIPT): Don't set.
* emulparams/shelf.sh (GENERATE_SHLIB_SCRIPT): Don't set.
* emulparams/shelf_nbsd.sh (GENERATE_SHLIB_SCRIPT),
(GENERATE_PIE_SCRIPT): Set.
* emulparams/shelf_uclinux.sh (GENERATE_SHLIB_SCRIPT): Set.
diff --git a/ld/emulparams/aarch64elf.sh b/ld/emulparams/aarch64elf.sh
index 8f68e517b4..5c70b55686 100644
--- a/ld/emulparams/aarch64elf.sh
+++ b/ld/emulparams/aarch64elf.sh
@@ -12,9 +12,6 @@ NO_REL_RELOCS=yes
TEMPLATE_NAME=elf
EXTRA_EM_FILE=aarch64elf
-GENERATE_SHLIB_SCRIPT=yes
-GENERATE_PIE_SCRIPT=yes
-
MAXPAGESIZE="CONSTANT (MAXPAGESIZE)"
ENTRY=_start
diff --git a/ld/emulparams/aarch64elf32.sh b/ld/emulparams/aarch64elf32.sh
index 5a08d9e29f..a94025a139 100644
--- a/ld/emulparams/aarch64elf32.sh
+++ b/ld/emulparams/aarch64elf32.sh
@@ -12,9 +12,6 @@ NO_REL_RELOCS=yes
TEMPLATE_NAME=elf
EXTRA_EM_FILE=aarch64elf
-GENERATE_SHLIB_SCRIPT=yes
-GENERATE_PIE_SCRIPT=yes
-
MAXPAGESIZE="CONSTANT (MAXPAGESIZE)"
ENTRY=_start
diff --git a/ld/emulparams/arcelf.sh b/ld/emulparams/arcelf.sh
index 625ec39779..b6d8f9fdf7 100644
--- a/ld/emulparams/arcelf.sh
+++ b/ld/emulparams/arcelf.sh
@@ -19,5 +19,3 @@ SDATA_START_SYMBOLS='__SDATA_BEGIN__ = . + 0x100;'
JLI_START_TABLE='__JLI_TABLE__ = .;'
OTHER_SECTIONS="/DISCARD/ : { *(.__arc_profile_*) }"
EMBEDDED=yes
-
-GENERATE_SHLIB_SCRIPT=yes
diff --git a/ld/emulparams/armelf.sh b/ld/emulparams/armelf.sh
index 0e3147c1f2..8977fd6fea 100644
--- a/ld/emulparams/armelf.sh
+++ b/ld/emulparams/armelf.sh
@@ -32,9 +32,6 @@ OTHER_READONLY_SECTIONS="
DATA_START_SYMBOLS="${CREATE_SHLIB+PROVIDE (}__data_start = .${CREATE_SHLIB+)};"
-GENERATE_SHLIB_SCRIPT=yes
-GENERATE_PIE_SCRIPT=yes
-
ARCH=arm
MACHINE=
MAXPAGESIZE="CONSTANT (MAXPAGESIZE)"
diff --git a/ld/emulparams/armelf_fbsd.sh b/ld/emulparams/armelf_fbsd.sh
index be88c2f2e0..4428b91a34 100644
--- a/ld/emulparams/armelf_fbsd.sh
+++ b/ld/emulparams/armelf_fbsd.sh
@@ -5,7 +5,7 @@ TEXT_START_ADDR=0x00010000
TARGET2_TYPE=got-rel
MAXPAGESIZE="CONSTANT (MAXPAGESIZE)"
+GENERATE_SHLIB_SCRIPT=yes
GENERATE_PIE_SCRIPT=yes
-
unset STACK_ADDR
unset EMBEDDED
diff --git a/ld/emulparams/armelf_nbsd.sh b/ld/emulparams/armelf_nbsd.sh
index 37e1a4afdd..45954597ee 100644
--- a/ld/emulparams/armelf_nbsd.sh
+++ b/ld/emulparams/armelf_nbsd.sh
@@ -3,5 +3,7 @@ MAXPAGESIZE="CONSTANT (MAXPAGESIZE)"
TEXT_START_ADDR=0x00008000
TARGET2_TYPE=got-rel
+GENERATE_SHLIB_SCRIPT=yes
+GENERATE_PIE_SCRIPT=yes
unset STACK_ADDR
unset EMBEDDED
diff --git a/ld/emulparams/armelf_vxworks.sh b/ld/emulparams/armelf_vxworks.sh
index 5f57535fee..e344209905 100644
--- a/ld/emulparams/armelf_vxworks.sh
+++ b/ld/emulparams/armelf_vxworks.sh
@@ -4,3 +4,4 @@ BIG_OUTPUT_FORMAT="elf32-bigarm-vxworks"
LITTLE_OUTPUT_FORMAT="$OUTPUT_FORMAT"
MAXPAGESIZE="CONSTANT (MAXPAGESIZE)"
source_sh ${srcdir}/emulparams/vxworks.sh
+GENERATE_SHLIB_SCRIPT=yes
diff --git a/ld/emulparams/armsymbian.sh b/ld/emulparams/armsymbian.sh
index 1959685f9b..183750a564 100644
--- a/ld/emulparams/armsymbian.sh
+++ b/ld/emulparams/armsymbian.sh
@@ -8,6 +8,8 @@ TARGET1_IS_REL=1
TARGET2_TYPE=abs
# On BPABI systems, program headers should not be mapped.
EMBEDDED=yes
+# Nonetheless, shared libraries are also supported
+GENERATE_SHLIB_SCRIPT=yes
# As for armelf.sh, but add the SymbianOS-specific
# .ARM.exidx$${Base,Limit} symbols.
diff --git a/ld/emulparams/elf32bfin.sh b/ld/emulparams/elf32bfin.sh
index 8d298b467c..6e08035b6f 100644
--- a/ld/emulparams/elf32bfin.sh
+++ b/ld/emulparams/elf32bfin.sh
@@ -6,7 +6,6 @@ TARGET_PAGE_SIZE=0x1000
ARCH=bfin
MACHINE=
TEMPLATE_NAME=elf
-GENERATE_SHLIB_SCRIPT=yes
EMBEDDED=yes
USER_LABEL_PREFIX=_
EXTRA_EM_FILE=bfin
diff --git a/ld/emulparams/elf32microblaze.sh b/ld/emulparams/elf32microblaze.sh
index f867018eb3..698adb7cf8 100644
--- a/ld/emulparams/elf32microblaze.sh
+++ b/ld/emulparams/elf32microblaze.sh
@@ -21,6 +21,3 @@ NOP=0x80000000
#OTHER_RELOCATING_SECTIONS='PROVIDE (_stack = _end + 0x1000);'
TEMPLATE_NAME=elf
-#GENERATE_SHLIB_SCRIPT=yes
-
-
diff --git a/ld/emulparams/score3_elf.sh b/ld/emulparams/score3_elf.sh
index 7be7883363..78401876e5 100644
--- a/ld/emulparams/score3_elf.sh
+++ b/ld/emulparams/score3_elf.sh
@@ -26,4 +26,3 @@ ARCH=score3
MACHINE=
ENTRY=_start
EMBEDDED=yes
-GENERATE_SHLIB_SCRIPT=yes
diff --git a/ld/emulparams/shelf.sh b/ld/emulparams/shelf.sh
index 63c2ff19dc..96c18c0750 100644
--- a/ld/emulparams/shelf.sh
+++ b/ld/emulparams/shelf.sh
@@ -9,7 +9,6 @@ MAXPAGESIZE=128
ARCH=sh
MACHINE=
TEMPLATE_NAME=elf
-GENERATE_SHLIB_SCRIPT=yes
EMBEDDED=yes
# These are for compatibility with the COFF toolchain.
ENTRY=start
diff --git a/ld/emulparams/shelf_nbsd.sh b/ld/emulparams/shelf_nbsd.sh
index 391399660d..57db803d00 100644
--- a/ld/emulparams/shelf_nbsd.sh
+++ b/ld/emulparams/shelf_nbsd.sh
@@ -11,5 +11,7 @@ DATA_START_SYMBOLS='PROVIDE (__data_start = .);';
ENTRY=_start
+GENERATE_SHLIB_SCRIPT=yes
+GENERATE_PIE_SCRIPT=yes
unset EMBEDDED
unset STACK_ADDR
diff --git a/ld/emulparams/shelf_uclinux.sh b/ld/emulparams/shelf_uclinux.sh
index a22c35a9a8..41044f028c 100644
--- a/ld/emulparams/shelf_uclinux.sh
+++ b/ld/emulparams/shelf_uclinux.sh
@@ -2,3 +2,4 @@ source_sh ${srcdir}/emulparams/shelf.sh
# We do not want a .stack section
unset STACK_ADDR
+GENERATE_SHLIB_SCRIPT=yes
--
Alan Modra
Australia Development Lab, IBM
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