Replace BLAS/LAPACK with OpenBLAS, add APK install docs

BLAS/LAPACK:
- Replace both libRblas.so and libRlapack.so with OpenBLAS post-build
- Remove libRlapack.so entirely and clear LAPACK_LIBS in Makeconf,
  matching RHEL 9's flexiblas approach (single library for BLAS+LAPACK)
- Use patchelf --replace-needed to repoint DT_NEEDED entries from
  libRlapack.so to libRblas.so in bundled modules (lapack.so, stats.so,
  Matrix.so, mgcv.so)
- Fix libRblas.so SONAME for correct package compilation
- Use OpenMP variant (openblas-openmp) on manylinux to match RHEL 9
  default; pthreads on musllinux (Alpine has no OpenMP variant)
- Add OpenBLAS verification tests (symbol check, no libRlapack.so,
  empty LAPACK_LIBS, sessionInfo, SONAME)

Docs:
- Add APK install instructions for musllinux in README
- Add BLAS/LAPACK handling section to portable-r README
- Remove EOL distros from portable-r README

Author: glin

README.md

@@ -295,6 +295,18 @@ and R auto-detects its install location so it can be extracted to any path.
 
 These builds require musl >= 1.2 (Alpine 3.20+, Void Linux musl, etc.).
 
+Two package formats are available: **APK** (Alpine Linux) and **tar.gz**
+(universal). The APK package automatically installs `ca-certificates`,
+`fontconfig`, and `ttf-dejavu` as dependencies, and installs R to
+`/opt/R/<version>/`. On non-Alpine musl distros, use the tarball.
+
+##### Install via APK package (Alpine Linux)
+
+```bash
+curl -O https://cdn.posit.co/r/musllinux_1_2/pkgs/r-${R_VERSION}_1_$(apk --print-arch).apk
+sudo apk add --allow-untrusted ./r-${R_VERSION}_1_$(apk --print-arch).apk
+```
+
 ##### Install via tarball
 
 Download and extract:
@@ -309,7 +321,7 @@ sudo mkdir -p /opt/R
 sudo tar xzf R-${R_VERSION}-musllinux_1_2*.tar.gz -C /opt/R
 ```
 
-Install system dependencies:
+Install system dependencies (only needed for tarballs; APK handles this automatically):
 ```bash
 # Runtime dependencies
 sudo apk add --no-cache ca-certificates fontconfig ttf-dejavu

builder/Dockerfile.manylinux_2_34

@@ -27,7 +27,7 @@ RUN dnf -y upgrade \
     libtool \
     make \
     ncurses-devel \
-    openblas-threads `# Bundled as libRblas.so (pthreads variant)` \
+    openblas-openmp `# Bundled as libRblas.so and libRlapack.so (matches RHEL 9 default)` \
     pango-devel \
     pcre-devel \
     pcre2-devel \
@@ -57,12 +57,10 @@ RUN chmod 0777 /opt
 # modern config directives. No source build needed (unlike Rocky 8).
 
 # Configure flags matching rhel-9.
-# --with-2025blas: Required for R >= 4.5.0. LAPACK 3.12.1 (Jan 2025) added new
-# BLAS routines (dgemmtr/zgemmtr). This flag compiles them into libRlapack
-# instead of libRblas, preserving the ability to swap BLAS implementations.
-# For manylinux_2_34, BLAS swapping is not supported (OpenBLAS is bundled
-# directly), but we keep this for consistency.
-# Harmlessly ignored on older R versions.
+# R compiles its own reference BLAS/LAPACK into libRblas.so and libRlapack.so.
+# The package script replaces both with OpenBLAS for performance. We don't use
+# --with-blas/--with-lapack here because it records the external library name
+# in Makeconf, which breaks package compilation on systems without OpenBLAS.
 ENV CONFIGURE_OPTIONS="\
     --enable-R-shlib \
     --with-tcltk \

builder/Dockerfile.musllinux_1_2

@@ -29,7 +29,7 @@ RUN apk update && apk add --no-cache \
     make \
     ncurses-dev \
     nfpm `# Builds APK packages from the portable R installation` \
-    openblas `# Bundled as libRblas.so (pthreads variant)` \
+    openblas `# Bundled as libRblas.so and libRlapack.so (pthreads; no OpenMP variant on Alpine)` \
     openjdk11-jdk \
     pango-dev \
     patch `# Needed by build.sh to apply R source patches` \
@@ -58,6 +58,10 @@ RUN chmod 0777 /opt
 
 # Configure flags for musllinux.
 # Same as manylinux_2_34, adapted for Alpine paths.
+# R compiles its own reference BLAS/LAPACK; the package script replaces both
+# with OpenBLAS. We don't use --with-blas/--with-lapack here because it records
+# the external library name in Makeconf, which breaks package compilation on
+# systems without OpenBLAS.
 # Tcl/Tk config files are in /usr/lib/ on Alpine (not /usr/lib64/).
 ENV CONFIGURE_OPTIONS="\
     --enable-R-shlib \

builder/package.manylinux_2_34

@@ -7,7 +7,7 @@ set -e
 # Called by build.sh after compile_r() installs R to $R_INSTALL_PATH.
 #
 # This script:
-# 1. Swaps reference BLAS with OpenBLAS (for performance)
+# 1. Replaces reference BLAS and LAPACK with OpenBLAS (for performance)
 # 2. Runs delocate_r.py to bundle system library dependencies
 # 3. Makes R_HOME self-detecting for relocatability
 #
@@ -18,38 +18,84 @@ set -e
 
 R_LIB_DIR="${R_INSTALL_PATH}/lib/R/lib"
 
-echo ">>> Phase 1: BLAS setup"
-# Replace reference BLAS with OpenBLAS for performance.
-# The manylinux_2_34 build uses internal shared BLAS (--with-blas is not set).
-# Swap it with system OpenBLAS so delocate_r bundles a real BLAS.
+echo ">>> Phase 1: BLAS/LAPACK setup"
+# Replace R's reference BLAS and LAPACK with OpenBLAS for performance, matching
+# how RHEL 9 uses flexiblas (a single library providing both BLAS and LAPACK).
+#
+# R compiles its own (slow) reference implementations into libRblas.so and
+# libRlapack.so. We replace libRblas.so with the system OpenBLAS library,
+# repoint all DT_NEEDED entries from libRlapack.so to libRblas.so, then remove
+# libRlapack.so entirely. This way, libRblas.so (OpenBLAS) provides both BLAS
+# and LAPACK, just like flexiblas does on RHEL 9.
+#
+# We don't use --with-blas/--with-lapack at configure time because it records
+# the external library name (e.g., -lopenblaso) in Makeconf. Unlike other
+# Makeconf libs (-lpcre2-8, -lbz2, etc.) which have consistent names across
+# distros, OpenBLAS names vary: libopenblaso.so on Rocky 9 vs. libopenblas.so
+# on Ubuntu/Alpine. Using -lRblas (R's own lib dir) avoids this portability
+# issue.
+#
+# Use the OpenMP variant (libopenblaso) to match RHEL 9's flexiblas default.
+# OpenMP OpenBLAS shares the thread pool with R's own OpenMP parallelism,
+# avoiding thread oversubscription.
+OPENBLAS_LIB=$(ls /usr/lib64/libopenblaso-r*.so 2>/dev/null | head -1)
+if [ -z "$OPENBLAS_LIB" ]; then
+  echo "ERROR: OpenBLAS OpenMP variant not found in /usr/lib64/"
+  ls /usr/lib64/libopenblas* 2>/dev/null || echo "  No libopenblas* files found"
+  exit 1
+fi
+echo "  Using OpenBLAS: $OPENBLAS_LIB"
 rm -f "${R_LIB_DIR}/libRblas.so"
-cp /usr/lib64/libopenblasp.so.0 "${R_LIB_DIR}/libRblas.so"
+cp "$OPENBLAS_LIB" "${R_LIB_DIR}/libRblas.so"
+echo "  Replaced libRblas.so with $(basename "$OPENBLAS_LIB")"
+
+# Repoint all DT_NEEDED entries from libRlapack.so to libRblas.so.
+# libR.so only links against libRblas.so, but several bundled modules link
+# against libRlapack.so at build time:
+#   - modules/lapack.so
+#   - library/stats/libs/stats.so
+#   - library/Matrix/libs/Matrix.so
+#   - library/mgcv/libs/mgcv.so
+# Without this, loading these modules at runtime would fail because
+# libRlapack.so no longer exists. Since OpenBLAS provides both BLAS and
+# LAPACK routines through libRblas.so, we redirect those references.
+echo "  Repointing libRlapack.so references to libRblas.so..."
+find "${R_INSTALL_PATH}" -name '*.so' -exec sh -c '
+  readelf -d "$1" 2>/dev/null | grep -q "libRlapack.so" && {
+    patchelf --replace-needed libRlapack.so libRblas.so "$1"
+    echo "    $(echo "$1" | sed "s|${R_INSTALL_PATH}/||")"
+  }
+' _ {} \;
+rm -f "${R_LIB_DIR}/libRlapack.so"
+echo "  Removed libRlapack.so"
+
+# Clear LAPACK_LIBS in Makeconf so it matches RHEL 9's flexiblas behavior.
+# BLAS_LIBS = -lRblas provides both BLAS and LAPACK routines.
+MAKECONF="${R_INSTALL_PATH}/lib/R/etc/Makeconf"
+sed -i 's|^LAPACK_LIBS = .*|LAPACK_LIBS = |' "$MAKECONF"
+echo "  Cleared LAPACK_LIBS in Makeconf"
 
 echo ">>> Phase 2: delocate_r repair"
 # Bundle non-allowed system library dependencies into the R installation
 # and rewrite RPATHs to use $ORIGIN-relative paths.
 #
 # LD_LIBRARY_PATH must include R's lib dir so ldd can locate libRblas.so
-# and libRlapack.so (which are internal to the R installation).
+# (which is internal to the R installation).
 export LD_LIBRARY_PATH="${R_LIB_DIR}:${LD_LIBRARY_PATH:-}"
 python3 /delocate_r.py "${R_INSTALL_PATH}"
 
-echo ">>> Phase 3: Fix BLAS/LAPACK SONAMEs for package compilation"
+echo ">>> Phase 3: Fix BLAS SONAME for package compilation"
 # After delocate_r repair, lib/R/lib/libRblas.so still has its original SONAME
-# (e.g., "libopenblasp.so.0"). When users compile R packages that link against
+# (e.g., "libopenblaso.so.0"). When users compile R packages that link against
 # -lRblas (from Makeconf's BLAS_LIBS), the linker records this SONAME. At load time,
-# the dynamic linker then fails to find "libopenblasp.so.0" on the target system.
+# the dynamic linker then fails to find "libopenblaso.so.0" on the target system.
 #
 # Fix: set the SONAME to match the filename so packages record "libRblas.so" as their
 # dependency, which can always be found in R's lib dir via LD_LIBRARY_PATH.
 if [ -f "${R_LIB_DIR}/libRblas.so" ]; then
   patchelf --set-soname libRblas.so "${R_LIB_DIR}/libRblas.so"
   echo "  Fixed libRblas.so SONAME"
 fi
-if [ -f "${R_LIB_DIR}/libRlapack.so" ]; then
-  patchelf --set-soname libRlapack.so "${R_LIB_DIR}/libRlapack.so"
-  echo "  Fixed libRlapack.so SONAME"
-fi
 
 echo ">>> Phase 4: Bundle Tcl/Tk library scripts"
 # The bundled libtcl8.6.so has hardcoded paths to Tcl scripts (e.g., /usr/share/tcl8.6

builder/package.musllinux_1_2

@@ -7,7 +7,7 @@ set -e
 # Called by build.sh after compile_r() installs R to $R_INSTALL_PATH.
 #
 # This script:
-# 1. Swaps reference BLAS with OpenBLAS (for performance)
+# 1. Replaces reference BLAS and LAPACK with OpenBLAS (for performance)
 # 2. Runs delocate_r.py to bundle system library dependencies
 # 3. Makes R_HOME self-detecting for relocatability
 #
@@ -16,32 +16,73 @@ set -e
 
 R_LIB_DIR="${R_INSTALL_PATH}/lib/R/lib"
 
-echo ">>> Phase 1: BLAS setup"
-# Replace reference BLAS with OpenBLAS for performance.
-# Swap it with system OpenBLAS so delocate_r bundles a real BLAS.
+echo ">>> Phase 1: BLAS/LAPACK setup"
+# Replace R's reference BLAS and LAPACK with OpenBLAS for performance, matching
+# how RHEL 9 uses flexiblas (a single library providing both BLAS and LAPACK).
+#
+# R compiles its own (slow) reference implementations into libRblas.so and
+# libRlapack.so. We replace libRblas.so with the system OpenBLAS library,
+# repoint all DT_NEEDED entries from libRlapack.so to libRblas.so, then remove
+# libRlapack.so entirely. This way, libRblas.so (OpenBLAS) provides both BLAS
+# and LAPACK, just like flexiblas does on RHEL 9.
+#
+# We don't use --with-blas/--with-lapack at configure time because it records
+# the external library name in Makeconf. Unlike other Makeconf libs
+# (-lpcre2-8, -lbz2, etc.) which have consistent names across distros, OpenBLAS
+# names vary: libopenblaso.so on Rocky 9 vs. libopenblas.so on Ubuntu/Alpine.
+# Using -lRblas (R's own lib dir) avoids this portability issue.
+#
 # Alpine installs OpenBLAS to /usr/lib/ (not /usr/lib64/).
-# Use the pthreads variant (libopenblasp) for consistency with other r-builds.
+# Use the pthreads variant (libopenblasp) since Alpine has no OpenMP variant.
+# On manylinux, we use the OpenMP variant to match RHEL 9's default.
 # On ARM64, the library is named libopenblas_armv8p-*.so instead of libopenblasp-*.so.
-rm -f "${R_LIB_DIR}/libRblas.so"
-OPENBLAS_LIB=$(ls /usr/lib/libopenblas*p-r*.so* 2>/dev/null | head -1)
+OPENBLAS_LIB=$(ls /usr/lib/libopenblas*p-r*.so 2>/dev/null | head -1)
 if [ -z "$OPENBLAS_LIB" ]; then
   echo "ERROR: OpenBLAS pthreads variant not found in /usr/lib/"
   ls /usr/lib/libopenblas* 2>/dev/null || echo "  No libopenblas* files found"
   exit 1
 fi
 echo "  Using OpenBLAS: $OPENBLAS_LIB"
+rm -f "${R_LIB_DIR}/libRblas.so"
 cp "$OPENBLAS_LIB" "${R_LIB_DIR}/libRblas.so"
+echo "  Replaced libRblas.so with $(basename "$OPENBLAS_LIB")"
+
+# Repoint all DT_NEEDED entries from libRlapack.so to libRblas.so.
+# libR.so only links against libRblas.so, but several bundled modules link
+# against libRlapack.so at build time:
+#   - modules/lapack.so
+#   - library/stats/libs/stats.so
+#   - library/Matrix/libs/Matrix.so
+#   - library/mgcv/libs/mgcv.so
+# Without this, loading these modules at runtime would fail because
+# libRlapack.so no longer exists. Since OpenBLAS provides both BLAS and
+# LAPACK routines through libRblas.so, we redirect those references.
+echo "  Repointing libRlapack.so references to libRblas.so..."
+find "${R_INSTALL_PATH}" -name '*.so' -exec sh -c '
+  readelf -d "$1" 2>/dev/null | grep -q "libRlapack.so" && {
+    patchelf --replace-needed libRlapack.so libRblas.so "$1"
+    echo "    $(echo "$1" | sed "s|${R_INSTALL_PATH}/||")"
+  }
+' _ {} \;
+rm -f "${R_LIB_DIR}/libRlapack.so"
+echo "  Removed libRlapack.so"
+
+# Clear LAPACK_LIBS in Makeconf so it matches RHEL 9's flexiblas behavior.
+# BLAS_LIBS = -lRblas provides both BLAS and LAPACK routines.
+MAKECONF="${R_INSTALL_PATH}/lib/R/etc/Makeconf"
+sed -i 's|^LAPACK_LIBS = .*|LAPACK_LIBS = |' "$MAKECONF"
+echo "  Cleared LAPACK_LIBS in Makeconf"
 
 echo ">>> Phase 2: delocate_r repair"
 # Bundle non-allowed system library dependencies into the R installation
 # and rewrite RPATHs to use $ORIGIN-relative paths.
 #
 # LD_LIBRARY_PATH must include R's lib dir so ldd can locate libRblas.so
-# and libRlapack.so (which are internal to the R installation).
+# (which is internal to the R installation).
 export LD_LIBRARY_PATH="${R_LIB_DIR}:${LD_LIBRARY_PATH:-}"
 python3 /delocate_r.py --policy musllinux "${R_INSTALL_PATH}"
 
-echo ">>> Phase 3: Fix BLAS/LAPACK SONAMEs for package compilation"
+echo ">>> Phase 3: Fix BLAS SONAME for package compilation"
 # After delocate_r repair, lib/R/lib/libRblas.so still has its original SONAME
 # (e.g., "libopenblasp.so.0"). When users compile R packages that link against
 # -lRblas (from Makeconf's BLAS_LIBS), the linker records this SONAME. At load time,
@@ -53,10 +94,6 @@ if [ -f "${R_LIB_DIR}/libRblas.so" ]; then
   patchelf --set-soname libRblas.so "${R_LIB_DIR}/libRblas.so"
   echo "  Fixed libRblas.so SONAME"
 fi
-if [ -f "${R_LIB_DIR}/libRlapack.so" ]; then
-  patchelf --set-soname libRlapack.so "${R_LIB_DIR}/libRlapack.so"
-  echo "  Fixed libRlapack.so SONAME"
-fi
 # Fix patchelf strtab mismatch (patchelf 0.18.0 bug with large binaries on musl)
 python3 -c "
 from pathlib import Path; import sys; sys.path.insert(0, '/')

builder/portable-r/README.md

@@ -174,6 +174,25 @@ Fontconfig requires special treatment because:
 
 The current builds use base images with fontconfig >= 2.14 (Rocky 9 ships 2.14.0, Alpine 3.21 ships 2.15.0), so no source build is needed. If a future manylinux build uses an older base image (e.g. with fontconfig 2.13), fontconfig 2.15.0 would need to be built from source. Version 2.15.0 is the latest release using autotools (2.16+ requires meson) and matches Ubuntu 24.04, RHEL 10, and Debian 13.
 
+### BLAS/LAPACK handling
+
+Portable builds use a post-build swap to replace R's reference BLAS and LAPACK with OpenBLAS. This differs from the standard r-builds approach and deserves explanation.
+
+**Standard r-builds** (e.g., `rhel-9`, `rhel-10`) use `--with-blas=flexiblas --with-lapack=flexiblas` at configure time. This works because the target system is the same distro, so FlexiBLAS is always available as an RPM dependency. Makeconf records `BLAS_LIBS = -lflexiblas`, and package compilation works because FlexiBLAS is installed.
+
+**Portable builds** cannot use `--with-blas` because:
+
+1. `--with-blas=<lib>` records the external library name in `etc/Makeconf` (e.g., `BLAS_LIBS = -lopenblasp`)
+2. When users compile R packages with Fortran code on a target system, `R CMD INSTALL` passes `$(BLAS_LIBS)` to the linker
+3. Unlike other Makeconf libraries (`-lpcre2-8`, `-llzma`, `-lbz2`, `-lz`, `-licuuc`) which have consistent `.so` names across all Linux distros, OpenBLAS does not: Rocky 9 names it `libopenblaso.so` (OpenMP variant), while Ubuntu and Alpine name it `libopenblas.so`. A `-lopenblaso` flag recorded on Rocky 9 fails on Ubuntu even with OpenBLAS installed.
+
+Instead, portable builds let R compile its own reference BLAS/LAPACK (so Makeconf says `BLAS_LIBS = -lRblas`), then replace the libraries post-build:
+
+1. **Phase 1** of `package.<platform>` replaces `libRblas.so` with a copy of the system OpenBLAS library, uses `patchelf --replace-needed` to repoint all `libRlapack.so` references to `libRblas.so`, removes `libRlapack.so`, and clears `LAPACK_LIBS` in Makeconf. This matches RHEL 9's flexiblas behavior where a single library provides both BLAS and LAPACK.
+2. **Phase 3** fixes the SONAME on `libRblas.so` from its original value (e.g., `libopenblaso.so.0`) to `libRblas.so`, so R packages that link against `-lRblas` record the correct DT_NEEDED entry
+
+This gives the same performance as `--with-blas` (optimized BLAS and LAPACK from OpenBLAS) while keeping Makeconf portable. The tradeoff is that users cannot swap to a different BLAS at runtime (noted in the Limitations section above).
+
 ## Adding a new manylinux version
 
 ### When to add a new version
@@ -229,7 +248,7 @@ The manylinux_2_34 build uses Rocky 9, which provides:
 RHEL 9+, Ubuntu 22.04+, Debian 12+, Fedora 36+, Amazon Linux 2023+
 
 **Not supported** (glibc < 2.34):
-RHEL 8, Ubuntu 20.04, Debian 10-11, Amazon Linux 2
+RHEL 8, Amazon Linux 2
 
 ### Parallel builds strategy
 

builder/portable-r/test-manylinux.sh

@@ -138,8 +138,42 @@ echo "=== HTTPS download from relocated path ==="
 # Restore original location for any further tests
 mv "${RELOCATED_DIR}" "${R_PREFIX}"
 
-echo "=== Verify libRblas/libRlapack SONAME ==="
-# libRblas.so must have SONAME "libRblas.so" (not the original "libopenblasp.so.0").
+echo "=== Verify OpenBLAS is linked (not reference BLAS) ==="
+# libRblas.so should be OpenBLAS (not R's reference implementation).
+# libRlapack.so should not exist (LAPACK is provided by OpenBLAS via libRblas.so).
+# Verify by checking for the openblas_get_config symbol, which only exists in OpenBLAS.
+if ! nm -D "${R_HOME}/lib/libRblas.so" 2>/dev/null | grep -q openblas_get_config; then
+  echo "FAIL: libRblas.so does not contain openblas_get_config -- not linked to OpenBLAS"
+  exit 1
+fi
+echo "  libRblas.so: contains OpenBLAS (OK)"
+# Verify libRlapack.so does not exist (all LAPACK routines come from libRblas.so)
+if [ -e "${R_HOME}/lib/libRlapack.so" ]; then
+  echo "FAIL: libRlapack.so should not exist (LAPACK is provided by libRblas.so)"
+  exit 1
+fi
+echo "  libRlapack.so does not exist (OK)"
+# Verify LAPACK_LIBS is empty in Makeconf (matches RHEL 9's flexiblas behavior)
+LAPACK_LIBS_VAL=$(grep '^LAPACK_LIBS' "${R_HOME}/etc/Makeconf" | sed 's/^LAPACK_LIBS = *//')
+if [ -n "$LAPACK_LIBS_VAL" ]; then
+  echo "FAIL: LAPACK_LIBS should be empty, got '$LAPACK_LIBS_VAL'"
+  exit 1
+fi
+echo "  Makeconf LAPACK_LIBS is empty (OK)"
+# Verify R reports the BLAS/LAPACK paths within R_HOME.
+# Since OpenBLAS provides both BLAS and LAPACK via libRblas.so, R should
+# report both BLAS and LAPACK pointing to libRblas.so.
+"${R_HOME}/bin/Rscript" -e '
+  si <- sessionInfo()
+  blas <- si$BLAS
+  lapack <- si$LAPACK
+  cat(sprintf("  BLAS: %s\n  LAPACK: %s\n", blas, lapack))
+  if (!grepl("libRblas", blas)) stop("sessionInfo()$BLAS does not point to libRblas.so")
+  if (!grepl("libRblas", lapack)) stop("sessionInfo()$LAPACK does not point to libRblas.so")
+'
+
+echo "=== Verify libRblas SONAME ==="
+# libRblas.so must have SONAME "libRblas.so" (not the original "libopenblaso.so.0").
 # If wrong, packages that link against -lRblas will record the wrong SONAME and
 # fail to load on systems without the matching library.
 RBLAS_SONAME=$(readelf -d "${R_HOME}/lib/libRblas.so" 2>/dev/null | sed -n 's/.*\(SONAME\).*\[\(.*\)\]/\2/p')
@@ -156,14 +190,14 @@ if ls "${R_PREFIX}"/lib/R/lib/.libs/*Rblas* 2>/dev/null; then
 fi
 echo "  libRblas.so not in .libs/ (OK)"
 
-# Verify testpkg.so links against libRblas.so (not libopenblasp.so.0)
+# Verify testpkg.so links against libRblas.so (not libopenblaso.so.0)
 TESTPKG_SO=$(find "${R_PREFIX}" -path "*/testpkg/libs/testpkg.so" 2>/dev/null | head -1)
 if [ -n "$TESTPKG_SO" ]; then
-  if readelf -d "$TESTPKG_SO" | grep -q "libopenblasp"; then
-    echo "FAIL: testpkg.so links against libopenblasp instead of libRblas"
+  if readelf -d "$TESTPKG_SO" | grep -q "libopenblaso"; then
+    echo "FAIL: testpkg.so links against libopenblaso instead of libRblas"
     exit 1
   fi
-  echo "  testpkg.so DT_NEEDED: OK (no libopenblasp reference)"
+  echo "  testpkg.so DT_NEEDED: OK (no libopenblaso reference)"
 fi
 
 echo "=== Rscript wrapper tests ==="